eVidyarthi

Main Menu
  • eVidyarthi
  • School
    • Class 6th
      • Maths Class 6
      • Science Class 6
      • Hindi Class 6
      • Vyakaran
      • English Class 6
      • English Grammar
      • Sanskrit Class 6
      • Geography Class 6
      • Civics Class 6
      • History Class 6
    • Class 7th
      • Maths Class 7
      • Science Class 7
      • Hindi Class 7
      • Vyakaran
      • English Class 7
      • English Grammar
      • Sanskrit Class 7
      • Geography Class 7
      • Civics Class 7
      • History Class 7
    • Class 8th
      • Maths Class 8
      • Science Class 8
      • Hindi Class 8
      • Vyakaran
      • English Class 8
      • English Grammar
      • Sanskrit Class 8
      • Geography Class 8
      • Civics Class 8
      • History Class 8
    • Class 9th
      • Maths Class 9
      • Science Class 9
      • Hindi Class 9
      • व्याकरण
      • English Class 9
      • English Grammar
      • Economics Class 9
      • Geography Class 9
      • Civics Class 9
      • History Class 9
      • Sanskrit Class 9
    • Class 10th
      • Maths Class 10
      • Science Class 10
      • Hindi Class 10
      • Vyakaran
      • English Class 10
      • English Grammar
      • Economics Class 10
      • Geography Class 10
      • Civics Class 10
      • History Class 10
      • Sanskrit Class 10
    • Class 11
      • Maths Class 11
      • English Class 11
      • Hindi Class 11
      • Accounts Class 11
      • Physics Class 11
      • Chemistry Class 11
      • Biology Class 11
      • Economics Class 11
      • Geography Class 11
      • History Class 11
      • Political Science Class 11
      • Sociology Class 11
    • Class 12
      • Maths Class 12
      • English Class 12
      • Hindi Class 12
      • Accounts Class 12
      • Physics Class 12
      • Chemistry Class 12
      • Biology Class 12
      • Economics Class 12
      • Geography Class 12
      • History Class 12
      • Political Science Class 12
      • Sociology Class 12
    • Close
  • School – हिन्दी माध्यम
    • Class 6
      • Hindi Class 6
      • English Grammar
      • Vyakaran
      • Ganit Class 6
      • Vigyan Class 6
      • Samajik Vigyan Class 6
      • English Class 6
      • संस्कृत Class 6
    • Class 7
      • Hindi Class 7
      • English Grammar
      • Vyakaran
      • गणित Class 7
      • विज्ञान Class 7
      • सामाजिक विज्ञान Class 7
      • English Class 7
      • Sanskrit Class 7
    • Class 8
      • Hindi Class 8
      • English Grammar
      • Vyakaran
      • गणित Class 8
      • विज्ञान Class 8
      • सामाजिक विज्ञान Class 8
      • English Class 8
      • Sanskrit Class 8
    • Class 9
      • Hindi Class 9
      • English Grammar
      • Vyakaran
      • गणित Class 9
      • विज्ञान Class 9
      • सामाजिक विज्ञान Class 9
      • English Class 9
      • Sanskrit Class 9
    • Class 10
      • Hindi Class 10
      • English Grammar
      • Vyakaran
      • गणित Class 10
      • विज्ञान Class 10
      • सामाजिक विज्ञान Class 10
      • English Class 10
      • Sanskrit Class 10
    • Class 11
      • गणित Class 11
      • English Class 11
      • Hindi Class 11
      • अर्थशास्त्र Class 11
      • भूगोल Class 11
      • इतिहास Class 11
      • राजनितिक विज्ञान
      • समाजशास्त्र Class 11
      • भौतिक विज्ञान Class 11
      • रसायन विज्ञान Class 11
      • जीव विज्ञान Class 11
    • Class 12
      • गणित Class 12
      • English Class 12
      • Hindi Class 12
      • अर्थशास्त्र Class 12
      • भूगोल Class 12
      • इतिहास Class 12
      • राजनितिक विज्ञान
      • समाजशास्त्र Class 12
      • भौतिक-विज्ञान Class 12
      • रसायन विज्ञान Class 12
      • जीव विज्ञान Class 12
    • Close
  • बिहार बोर्ड
    • Class 6
      • हिंदी Class 6
      • Vyakaran
      • English Grammar
      • गणित Class 6
      • विज्ञान Class 6
      • English Class 6
      • सामाजिक विज्ञान Class 6
      • Sanskrit Class 6
    • Class 7
      • हिंदी Class 7
      • Vyakaran
      • English Grammar
      • गणित Class 7
      • विज्ञान Class 7
      • English Class 7
      • सामाजिक विज्ञान Class 7
      • Sanskrit Class 7
    • Class 8
      • हिंदी Class 8
      • Vyakaran
      • English Grammar
      • गणित Class 8
      • विज्ञान Class 8
      • English Class 8
      • सामाजिक विज्ञान Class 8
      • Sanskrit Class 8
    • Class 9
      • हिंदी Class 9
      • Vyakaran
      • English Grammar
      • गणित Class 9
      • विज्ञान Class 9
      • English Class 9
      • सामाजिक विज्ञान Class 9
      • Sanskrit Class 9
    • Class 10
      • हिंदी Class 10
      • Vyakaran
      • English Grammar
      • गणित Class 10
      • विज्ञान Class 10
      • English Class 10
      • सामाजिक विज्ञान Class 10
      • Sanskrit Class 10
    • Close
  • एमपी बोर्ड
    • Class 6
      • हिंदी Class 6
      • Vyakaran
      • English Grammar
      • English Class 6
      • संस्कृत Class 6
      • गणित Class 6
      • विज्ञान Class 6
      • सामाजिक विज्ञान Class 6
    • Class 7
      • हिंदी Class 7
      • Vyakaran
      • English Grammar
      • English Class 7
      • संस्कृत Class 7
      • गणित Class 7
      • विज्ञान Class 7
      • सामाजिक विज्ञान Class 7
    • Class 8
      • हिंदी Class 8
      • Vyakaran
      • English Grammar
      • English Class 8
      • संस्कृत Class 8
      • गणित Class 8
      • विज्ञान Class 8
      • सामाजिक विज्ञान Class 8
    • Class 9
      • हिंदी Class 9
      • Vyakaran
      • English Grammar
      • English Class 9
      • गणित Class 9
      • संस्कृत Class 9
      • विज्ञान Class 9
      • सामाजिक विज्ञान Class 9
    • Class 10
      • हिंदी Class 10
      • Vyakaran
      • English Grammar
      • English Class 10
      • गणित Class 10
      • संस्कृत Class 10
      • विज्ञान Class 10
      • सामाजिक विज्ञान Class 10
    • Close
  • English
    • Basic English Grammar
    • Basic English Speaking
    • English Vocabulary
    • English Idioms & Phrases
    • Personality Enhancement
    • Interview Skills
    • Close
  • Softwares
    • Microsoft Word
    • PhotoShop
    • Excel
    • Illustrator
    • PowerPoint
    • Close
Maths Class 7 || Menu
  • MCQ Maths Class 7
  • Notes Maths Class 7
  • NCERT Solutions
  • Important Formulas Maths Class 7
  • Sample Paper Maths Class 7
  • Previous Year Paper Maths Class 7
  • Book Maths Class 7
  • Integers
    • Ex 1.1
    • Ex 1.2
    • Ex 1.3
    • Ex 1.4
    • MCQs
    • Close
  • Fractions and Decimals
    • Ex 2.1
    • Ex 2.2
    • Ex 2.3
    • Ex 2.4
    • Ex 2.5
    • Ex 2.6
    • Ex 2.7
    • MCQs
    • Close
  • Data Handling
    • Ex 3.1
    • Ex 3.2
    • Ex 3.3
    • Ex 3.4
    • MCQs
    • Close
  • Simple Equations
    • Ex 4.1
    • Ex 4.2
    • Ex 4.3
    • Ex 4.4
    • MCQs
    • Close
  • Lines and Angles
    • Ex 5.1
    • Ex 5.2
    • MCQs
    • Close
  • Triangle and its Properties
    • Ex 6.1
    • Ex 6.2
    • Ex 6.3
    • Ex 6.4
    • Ex 6.5
    • MCQs
    • Close
  • Congruence of Triangles
    • Ex 7.1
    • Ex 7.2
    • MCQs
    • Close
  • Comparing Quantities
    • Ex 8.1
    • Ex 8.2
    • Ex 8.3
    • MCQs
    • Close
  • Rational Numbers
    • Ex 9.1
    • Ex 9.2
    • MCQs
    • Close
  • Practical Geometry
    • Ex 10.1
    • Ex 10.2
    • Ex 10.3
    • Ex 10.4
    • Ex 10.5
    • MCQs
    • Close
  • Perimeter and Area
    • Ex 11.1
    • Ex 11.2
    • Ex 11.3
    • Ex 11.4
    • MCQs
    • Close
  • Algebraic Expressions
    • Ex 12.1
    • Ex 12.2
    • Ex 12.3
    • Ex 12.4
    • MCQs
    • Close
  • Exponents & Powers
    • Ex 13.1
    • Ex 13.2
    • Ex 13.3
    • MCQs
    • Close
  • Symmetry
    • Ex 14.1
    • Ex 14.2
    • Ex 14.3
    • MCQs
    • Close
  • Visualising Solid Shapes
    • Ex 15.1
    • Ex 15.2
    • Ex 15.3
    • Ex 15.4
    • MCQs
    • Close
Share on WhatsApp

Class 7 Ex. 8.1 Maths NCERT Solutions

Ads

Solutions For All Chapters Maths Class 7

NCERT Solutions for Class 7 Maths Chapter 8 Comparing Quantities Ex 8.1

Ex 8.1 Class 7 Maths Question 1.
Find the ratio of:

(a) ₹ 5 to 50 paise

(b) 15 kg to 210 g

(c) 9 m to 27 cm

(d) 30 days to 36 hours

Solution:

(a) ₹ 5 to 50 paise
Converting the given quantities into same units, we have
₹ 5 = 5 × 100 = 500 paise
∴ ₹ 5 : 50 paise
= 500 paise : 50 paise [∵ ₹ 1 = 100 paise]
= 10 : 1
So, required ratio is 10 : 1.

(b) 15 kg to 210 g
Converting the given quantities into same units, we have
15 kg = 15 × 1000
= 15000 g [∵ 1 kg = 1000 g]
∴ 15 kg : 210 g = 15000 g : 210 g
= 1500 : 21
= 500 : 7
So, the required ratio is 500 : 7.

(c) 9 m to 27 cm
Converting the given quantities into same units, we have
9 m = 9 × 100 = 900 cm
∴ 9m: 27 cm = 900 cm : 27 cm [∵ 1 m = 100 cm]
= 100 : 3
So, the required ratio is 100 : 3.

(d) 30 days to 36 hours
Converting the given quantities into same
units, we have
30 days = 30 × 24 hours [ ∵ 1 day = 24 hours]
= 720 hours
∴ 30 days : 36 hours
= 720 hours : 36 hours = 20:1
So, the required ratio is 20 : 1.

Ex 8.1 Class 7 Maths Question 2.
In a computer lab, there are 3 computers for every 6 students. How many computers will be needed for 24 students?

Solution:

Using Unitary Method, we have
6 students require 3 computers
∴ 1 student will require = 3/6 computers
∴ 24 students will require = 3/6 x 24 computers
= 3 × 4 computers = 12 computers
Hence the number of computers required = 12.

Ex 8.1 Class 7 Maths Question 3.
Population of Rajasthan = 570 lakhs and population of UP = 1660 lakhs.
Area of Rajasthan = 3 lakh km² and area of UP = 2 lakh km².
(i) How many people are there per km2 in both these States?
(ii) Which State is less populated?

Solution:

Given:
Population of Rajasthan = 570 lakhs
Population of UP = 1660 lakhs
Area of Rajasthan = 3 lakh km²
Area of UP = 2 lakh km²

(i) Number of people per km² of Rajasthan 5
= 570 lakhs / 3 lakh km²
= 190 per km²
Number of people in UP = 1660 lakhs
Area of UP = 2 lakh km2
Number of people per km2 of UP
= =1660 lakhs / 2 lakh km² =830 per km²
Since 190 per km²< 830 per km²
(ii) Rajasthan is less populated state.

Ads

Android App

eVidyarthi

Evidyarthi on Facebook

Like us on Facebook

YouTube Channels

Social Science Class 6
Social Science Class 8
Learn English
English Through हिन्दी
Job Interview Skills
English Grammar
हिंदी व्याकरण - Vyakaran
Mathematics Class 6th
Social Science Class 6
Science Class 6th
हिन्दी Class 6th
Mathematics Class 7th
Science Class 7th
हिन्दी Class 7th
Mathematics Class 8th
Social Science Class 8
Social Science Class 8
Science Class 8th
हिन्दी Class 8th
Mathematics Class 9th
English Class 9th
Science Class 9th
Mathematics Class 10th
English Class 10th
Mathematics Class XI
Chemistry Class XI
Accountancy Class 11th
Accountancy Class 12th
Mathematics Class 12th
Microsoft Word
Microsoft Excel
Microsoft PowerPoint
Adobe PhotoShop
Adobe Illustrator
Learn German
Learn French
IIT JEE
Privacy Policies, Contact Us
Copyright © 2022 eVidyarthi and its licensors. All Rights Reserved.