4
Q:

# Alloy A contains 40% gold and 60% silver. Alloy B contains 35% gold and 40% silver and 25% copper. Alloys A and B  are mixed in the ratio of 1:4 .What is the ratio of gold and silver in the newly formed alloy is?

 A) 20% and 30% B) 36% and 44% C) 25% and 35% D) 49% and 36%

Explanation:

Assume the weight of alloy a is 100 kg

$\inline&space;\fn_jvn&space;\therefore$  The weight of alloy B is 400kg

$\inline&space;\fn_jvn&space;\therefore$               Gold          silver         copper

A       40kg          60kg          0kg

B      140kg         160kg        100kg

total    180kg          220kg        100kg

$\inline&space;\fn_jvn&space;\therefore$ Ratio of gold and silver in new alloy =$\inline&space;\fn_jvn&space;\frac{180}{500}:\frac{200}{500}$

= 36% :44%

Q:

The sum of three numbers is 98. If the ratio of the first to the second is 2:3. And that of the second to the third is 5:8, then the second number is:

 A) 10 B) 15 C) 20 D) 30

Explanation:

Let the three parts M, N, O.
Then, M:N = 2:3 and N:O = 5:8
= (5 x 3/5) : (8 x 3/5) = 3:24/5

M:N:O = 2:3:24/5

= 10:15:24 => N = 98 x 15/49 = 30.

2 44
Q:

Rs. 2600 is divided into three parts A, B and C. How much A is more than C if their ratio is 1/2:1/3:1/4 ?

 A) 600 B) 300 C) 150 D) 75

Explanation:

1/2:1/3:1/4 = 6:4:3

As the difference is 3

=> 3/13x2600 = 600

2 99
Q:

If 6 men and 3 boys working together, can do four times as much work per hour as a man and a boy together. Find the ratio of the work done by a man and that of a boy for a given time  ?

 A) 1 : 2 B) 2 : 1 C) 3 : 1 D) 1 : 3

Explanation:

6M + 3B = 4(1M + 1B)
6M + 3B = 4M + 4B
2M = 1B

M/B = 1/2

5 155
Q:

If k : l = 4 : 3 and l : m = 5 : 3, then find k : l : m ?

 A) 18 : 24 : 11 B) 9 : 15 : 1 C) 20 : 15 : 9 D) 21 : 7 : 3

Explanation:

Given k : l = 4 : 3
l : m = 5 : 3

Then k : l : m = 20 : 15 : 9

4 224
Q:

A sum is divided among K, L and M in such a way that for each rupee K gets, L gets 45 paisa and M gets 30 paisa. If the share of L is Rs. 27,  what is the total amount  ?

 A) Rs. 159 B) Rs. 96 C) Rs. 147 D) Rs. 105

Explanation:

K : L : M = 100 : 45 : 30
= 20 : 9 : 6

Given L share is 27

=> 9  ------  27
35 ------  ?

=> 105