## RS Aggarwal Class 8 Math Ninth Chapter Percentage Exercise 9B Solution

## EXERCISE 9B

### OBJECTIVE QUESTIONS

#### Tick (√) the correct answer in each of the following:

**(2) 0.8% when expressed as a decimal, is**

**(3) 6 : 5 when expressed as a percentage, is**

**(4) 5% of a number is 9. The number is**

Solution: Let the required number be x. Then,

5% of x = 9

Ans: (d)

**(5) What per cent of 90 is 120?**

**(6) What percent of 10 kg is 250g?**

Ans: Here 10 kg = 10,000 g

**(7) 40% of ?= 240**

**(8) ?% of 400 = 60**

Ans: (c)

**(9) (180% of ?) ÷ 2 =504**

Ans: (d)

**(10) 20% of Rs 800 = ?**

**(11) In an examination, Nitin gets 98 marks. This amounts to 56% of the maximum marks. What are the maximum marks?**

Solution: Let the maximum marks be x.

Ans: (c)

**(12) A number is first increased by 10% and then reduce by 10%. The number **

Ans: (b) decreases by 1%

**(13) A period of 4 hours 30 min is what per cent of a day?**

Ans: Here 4 hours 30 min = (240 + 30) = 270 min

A day = 24 hours = (24 × 60) = 1440 min

**(14) In an examination, 65% of total examinees passed. If the number of failures is 420, the total number of examinees is **

Solution: Let the total number of examinees be 100.

Percentage of examinees passed = 65%

Percentage of examinees failed = (100 – 65)% = 35%

Ans: (c)

**(15) A number exceeds 20% of itself by 40. The number is**

Solution: Let the number be x.

Ans: (a)

**(17) 0.05 is what per cent of 20?**

**(18) One-third of 1206 is what per cent of 134?**

**(19) x% of y % of?**

Solution: Let the required number be z. Then,

x% of y = y% of z

Ans: (a)

**(20) What per cent of 2/7 is 1/35?**