# Percentages Quiz Set 005

### Question 1

A carton contains 5000 led bulbs, some of them are red, some green and others are blue. How many are green if 6% are red and 4% are blue?

A

4500.

B

4600.

C

4400.

D

4700.

Soln.
Ans: a

The percentage of green is 100 - (6 + 4) = 90. So number of green bulbs = \$90/100\$ × 5000 = 4500.

### Question 2

A bag contains 780 red, 2160 green and 3060 blue marbles. What percentage of the total is the most visible color in the bag?

A

51 %.

B

61 %.

C

41 %.

D

71 %.

Soln.
Ans: a

By inspection, blue is the most visible color. The percentage of blue is \$3060/{780 + 2160 + 3060}\$ × 100 = 51%.

### Question 3

A sample of alcohol has 80% water, and another sample has 70% water. If equal volumes of both the samples are combined, what is the percentage of water in the new sample?

A

75 %.

B

77 %.

C

73 %.

D

79 %.

Soln.
Ans: a

If 100 units of both alcohol are combined, there will be 150 units of water in 200 units of the new sample. The percentage of water is \$150/200\$ × 100 = 75%.

### Question 4

A carton contains 8000 led bulbs, some of them are red, some green and others are blue. How many are green if 3% are red and 5% are blue?

A

7360.

B

7460.

C

7260.

D

7560.

Soln.
Ans: a

The percentage of green is 100 - (3 + 5) = 92. So number of green bulbs = \$92/100\$ × 8000 = 7360.

### Question 5

One number is 300 more than the other, and it is 75% of the sum of them. What is the number?

A

450.

B

550.

C

350.

D

650.

Soln.
Ans: a

Let the numbers be x and x - 300. We have been given x = \$75/100\$ × (x + x - 300), which gives 100x = 75 × (2x - 300), solving, we get x = 450. 