# Averages Quiz Set 001

### Question 1

A box contains 5 marbles each having a weight of 156 grams. The box also contains 25 marbles each having a weight of 114 grams. What is the average weight of all the marbles in the box?

A

121 grams.

B

122 grams.

C

120 grams.

D

119 grams.

Soln.
Ans: a

The weighted average = \${5 × 156 + 25 × 114}/30\$, which equals \${780 + 2850}/30\$ = 121.

### Question 2

The average number of visitors at a zoo on a Monday is 96, whereas it is 156 on other days of the week. What will be the average number of visitors in a 30-day month that begins on a Monday?

A

146.

B

147.

C

145.

D

144.

Soln.
Ans: a

The month begins on a Monday, so there will be 5 Mondays. The average = \${5 × 96 + 25 × 156}/30\$, which equals \${480 + 3900}/30\$ = 146.

### Question 3

The sales(in rupees) of a gift shop for six consecutive days is 1254, 5016, 4230, 876, 984 and 2076. What is the overall average sale for these six days?

A

Rs.2406.

B

Rs.2412.

C

Rs.2400.

D

Rs.2418.

Soln.
Ans: a

The total sale on first six days is 1254 + 5016 + 4230 + 876 + 984 + 2076 = 14436. The average for 6 days is: 14436/6, which gives Rs. 2406.

### Question 4

The average number of visitors at a zoo on a Monday is 90, whereas it is 84 on other days of the week. What will be the average number of visitors in a 30-day month that begins on a Monday?

A

85.

B

86.

C

84.

D

83.

Soln.
Ans: a

The month begins on a Monday, so there will be 5 Mondays. The average = \${5 × 90 + 25 × 84}/30\$, which equals \${450 + 2100}/30\$ = 85.

### Question 5

There are three sections in school with 20, 40 and 40 students respectively. The average weight of a student in these sections, respectively, is 6, 2 and 4 Kg. What is the average weight of all the the students of the combined sections?

A

\$3{3/5}\$.

B

\$3{61/100}\$.

C

\$3{59/100}\$.

D

\$3{29/50}\$.

Soln.
Ans: a

The sums of the weights of all the students is 20 × 6 + 40 × 2 + 40 × 4 = 360. The required average = 360/total students = \$360/{20 + 40 + 40}\$ = \${18/5}\$, which is same as: \$3{3/5}\$.