Exercise 3.4 - Chapter 3 Ratio and Proportion Term 1 6th Maths Guide Samacheer Kalvi Solutions - SaraNextGen [2024-2025]

Updated By SaraNextGen

On April 24, 2024, 11:35 AM

Ex $3.4$
Question $1 .$
Fill in the blanks.
(i) If the cost of 3 pens is ₹ 18 , then the cost of 5 pens is
(ii) If Karkuzhali earns ₹ 1800 in 15 days, then she earns ₹ 3000 in days
Solution:
(i) ₹ 30
Hint: $5 \times \frac{18}{3}=5 \times 6=₹ 30$
(ii) 25 Days
Hint:
$\begin{aligned}
&\frac{1800}{3000}=\frac{15}{x} \\
&\Rightarrow \mathrm{x}=\frac{15 \times 3000}{1800}=25 \text { days }
\end{aligned}$

Question 2 .
Say True or False.
(i) If the weight of 40 books is $8 \mathrm{~kg}$, then the weight of 15 books is $3 \mathrm{~kg}$.
(ii) A car travels $90 \mathrm{~km}$ in 3 hours with constant speed, It will travel $140 \mathrm{~km}$ in 5 hours at the same speed.
Solution:
(i) True
(ii) False

Question $3 .$
If a person reads 20 pages of a book in 2 hours, how many pages will he read in 8 hours at the same speed.
Solution:
Pages read in 2 hours $=20$
Then pages read in 1 hour $=\frac{20}{2}=10$ pages.

Pages will be read in 8 hours $=8 \times 10=80$ pages.
Number of pages will be read in 8 hrs $=80$ pages
 

Question 4 .
The cost of 15 chairs is Rs 7500 . Find the number of such chairs that can be purchased for Rs $12000 ?$
Solution:
Cost of 15 chairs $=$ Rs 7500
Cost of 1 chair $=$ Rs $\frac{7500}{15}=$ Rs 500
Numher of chairs that can he purchased for Rs $12000=\frac{12000}{500}$
$=24$ chairs
 

Question 5 .
A car covers a distance of $125 \mathrm{~km}$ in $5 \mathrm{~kg}$ of LP Gas. How much distance will it cover in $3 \mathrm{~kg}$ of LP Gas?
Solution:
With $5 \mathrm{~kg}$ LP Gas distance covered $=125 \mathrm{~km}$
With $1 \mathrm{~kg}$ LP Gas distance covered $=\frac{125}{5}=25 \mathrm{~km}$
With $3 \mathrm{~kg}$ LP Gas distance covered $=25 \times 3=75 \mathrm{~km}$.
$75 \mathrm{~km}$ can be covered with $3 \mathrm{~kg}$ LP Gas.
 

Question 6 .
Cholan walks $6 \mathrm{~km}$ in 1 hour at constant speed. Find the distance covered by him in $20 \mathrm{minutes}$ at the same speed.
Solution:
In 1 hour ( 60 minutes), distance covered $=6 \mathrm{~km}$
In 1 minute, distance covered $=\frac{6 k m}{60 m i n}=\frac{6000 m}{60}$
$=100 \mathrm{~m}$
In 20 minutes, distance covered $=20 \times 100 \mathrm{~m}=2000 \mathrm{~m}=2 \mathrm{~km}$
 

Question 7 .
The number of correct answers given by Kaarmugilan and Kavitha in a quiz competition is in the ratio $10: 11 .$ If they had scored a total of 84 points in the competition, then how many points did Kavitha get?

Solution:
Correct answers given by Kaarmugilan and Kavitha are in the ratio $10: 11$
Total of 84 points will be divided into $10+11=21$ equal parts
Points scored by Kavitha $=\frac{11}{21} \times 84=44$ points
Kavitha scored 44 points in the quiz.

Question 8 .
Karmegam made 54 runs in 9 overs and Asif made 77 runs in 11 overs. Whose run rate is better?
(run rate $=$ ratio of runs to overs)
Solution:
Karmegam Runs made in 9 overs $=54$
Runs made in 1 over $=\frac{54}{9}=6$ runs
Asif Runs made in 11 overs $=77$ Runs made in 1 over $=\frac{77}{11}=7$ runs
$\therefore$ Asif's run rate is better than Karmegam.

Question $9 .$
You purchase 6 apples for ₹ 90 and your Mend purchases 5 apples for ₹ 70 . Whose purchase is better?
Solution:
In my purchase cost of 6 apples $=₹ 90$
Cost of 1 apple $=\frac{90}{6}=₹ 15$
In my friend's purchase cost of 5 apples $=₹ 70$
Cost of 1 apple $=\frac{70}{5}=₹ 14$
My friend buy for lower prize.
My friend's purchase is a better buy.

Objective Type Questions
Question 10 .
If a Barbie doll costs Rs 90 , then the cost of 3 such dolls is Rs.......
(a) 260
(b) 270
(c) 30
(d) 93
Solution:
(b) 270

Question 11 .
If 8 oranges cost ₹ 56 , then the cost of 5 oranges is ₹
(a) 42
(b) 48
(c) 35
(d) 24
Solution:
(c) 35

Question 12 .
If a man walks $2 \mathrm{~km}$ in 15 minutes, then he will walk $\mathrm{km}$ in 45 minutes.
(a) 10
(b) 8
(c) 6
(d) 12
Solution:
(c) 6