It is very important to practice all the questions given in CBSE NCERT textbooks in subjects like math, science, English, etc. However, sometimes, you may get stuck with a few problems or a concept not knowing what to do next. To make it easier for you, we have come up with a set of solutions for all the questions chapter wise and subject wise by experienced subject experts.
Important questions based on NCERT syllabus for Class 7 Chapter 5 - Lines and Angles:
Question 1: The sum of four consecutive multiples of 9 is 378. Find these multiples.
Let the first number = 9x,
second consecutive number = 9x+9
Third consecutive number = 9x+18,
fourth consecutive number = 9x+27
So, 9x + 9x+9+9x+18+9x+27 = 378
36x+54 = 378;
So, Let the first number =9x= 9×9=81;
Second consecutive number =9x+9=90;
Third consecutive number =9x+18=99;
fourth consecutive number =9x+27=108.
Question 2: A carton has twenty chocolates worth rupees 100. The carton consists of Cadbury shots worth rupees 3 each and 5star worth rupees 11 each. How many 5star chocolates are there in the carton?
Let the no. of Cadbury shots = y
Then no. of 5star chocolates = 20-y
As given in question, Cadbury shots worth rupees 3 and 5star worth rupees 11.
Total worth of chocolates in carton=100
⇒ y ×3+(20-y)×11=100
⇒ y= 15
There are 15 Cadbury shots and 5 5star.
Question 3: In a triangle ABC , angle A is half of B and angle C is thrice of A . Find the value of angle A,B and C.
As we know that sum of all angles in a triangle is 180⁰.
Let the value of angle B=y⁰;
Value of angle A = y⁰/2
Value of angle C = 3y⁰/2
⇒ y⁰+y⁰/2+3y⁰/2 = 180⁰
⇒ 3y⁰ = 180⁰
⇒ y⁰= 60⁰
So, Value of angle A = y⁰/2 = 30⁰
Value of angle C = 3y⁰/2 = 90⁰.
Question 4: Arjun has thrice as many rupees as Prateek, and Shubhendu has half as many has Arjun and Prateekput together. Arjun has 130 rupees which is 120 rupees less than Shubhendu. How many does each of them have?
Let Prateek has x rupees.
Therefore Arjun has 3x rupees.
Shubhendu rupees=(3x+x) × 1/2=13+120=250.
⇒ x is 4x × 1/2=250
Therefore x has 150 rupees that means Prateek has 125rupees.
Arjun has 3x = 125×3 = 375 rupees.
Question 5: Ethan is responsible for buying a week's supply of food and medication for the dogs and cats at a local shelter. The food and medication for each dog costs twice as much as those supplies for a cat. He needs to feed 164 cats and 24 dogs. Her budget is $4240.
How much can Ethan spend on each dog for food and medication?
Let the expenditure on a cat = y.
The expenditure on a dog =2y.
So, for 24dogs the total expenditure = 24×2×22.08 = $1060