AMCAT Ratio and Proportion Quiz-1

Ans: 36000
Sol:
Income ratio = 8:5
Expenditure = 5:3
Savings = 11000 : 9000
By multiplication we get,
(5 x 9000) - (3 x 11000) = 12,000
Also, (5 x 5) - (8 x 3) = 1
So, 1 unit = 12000
Now, difference in income = 8-5 = 3 unit = 3 x 12000 = 36000

Correct Option: 1:3
Let the ratios be 17a : 14a : 23a
From the question 17a + 14a + 23a = 432
54a = 432
a = 432/54 = 8
A= 136
B= 112
C= 184
Required ratio = 24 : 72
= 1:3

Correct Option: 108

Total money = 30 + 60 = 90
In this question the total money is given so we need to multiply the value of the coins in the ratio.
20 × 0.10 x + 16 × 0.25x + 18 × 0.50x = 90
2x + 4x + 9x = 90
15 x = 90
x = 6
Number of 50 paise coins = 18 × 6 = 108

Correct Option: 385, 330

Sum of terms = (6+ 7) = 13.
First part = Rs. ( 715 × 6/13) = Rs. 330
Second part = Rs. ( 715 × 7/13 ) = Rs. 385.

Correct Option: 6:1

Let the cost price of one shirt = x Rs., the cost price of one jeans = y Rs.
According to the question,
3x + 4y = 2600 ....1
6y + 9x = 4200
3x + 2y = 1400 ....2
After solving these 2 equation,
x = 100 Rs. , y = 600 Rs.
Ratio = 600 : 100 = 6 : 1

Ans: 1120
Sol:
Let, no of boys 9x and girls 7x
Now, 7x = 490
x = 490/7 = 70
Total no of people = 9x + 7x = 16x
= 16* 70 = 1120

Ans: 120
Sol:
The ratio can be expressed as =(2/8) : (3/16) : (4/24)
LCM of 8, 16 and 24 = 48
So, new ratio
12: 18: 8 = 6: 9: 4
Third part = 4/19 * 570
= 120

Correct Option: 21 : 32 : 54
Let the investment of Suhani be ₹ x,
that of Saloni be ₹ y and that of Kirti be ₹ z respectively.
Then, 12x : 9y : 6z = 7 : 8 : 9
or, 12x/9y = 7/8
32x = 21y
21y/32
And 9y/6z = 8/9
27y = 16z
27y/16
So, x : y : z = 21y/32 : y : 27y/16 = 21 : 32 : 54

Correct Option: 36000

Let's take Sunil's income as ₹ 100, then
Akshay : Sunil : Paresh = 150 : 100 : (120 × 150)/100
= 15 : 10 : 18
Paresh's share = 18/43 × 86000 = ₹ 36000

Correct Option: 12:7

Total No. of boys = 3600 – 1400 = 2400
Respective ratio = 24000 : 1400 = 12 : 7.