Page 122 - ICSE Math 6

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\ Required percentage = ×100% = 80%
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Alternatively, percentage of rotten apples = 24 ×100% = 20%
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\ Percentage of eatable apples = (100 – 20)% = 80%

EXERCISE 9.2

1. Out of 30,000 voters in a constituency, 65% voted. Find the number of voters who did not vote.

2. In an airplane, 360 out of 600 passengers are women. What percentage of passengers are men?
3. Mayank is 48 kg in weight and he weighs 20% more than Sharad. What is Sharad’s weight?
4. In a class, 25% of the total students are absent. If 45 students are present, then what is the total
strength of the class?

5. In a competitive exam, out of 270 students, 115 students scored grade A, 127 students scored
grade B, 17 students just passed and the rest failed. Find the percentage of failures.

AT A GLANCE
¾ Per cent means ‘out of hundred’ or ‘for every hundred’. It is denoted by the symbol ‘%’.
x
¾ To express x as a percentage of y, multiply by 100%.
y
¾ To find the percentage of a given quantity, express the given percentage as a fraction with the
denominator 100 and multiply by the given number.
¾ To find a number from its given percentage, express the given percentage as a fraction with the
denominator 100 and then divide the given number by the fraction.

MENTAL MATHS

1. Write True or False.

(a) 9 out of 100 is 90 per cent. (b) 99 out of 100 is 99 per cent.
(c) 17 per cent is 17 out of 100 (d) 44 per cent is 100 out of 44.
2. Fill in the blanks.

(a) 50 m as a percentage of 100 m is _______%.
(b) 10 s as a percentage of 5 s is _______%.
(c) 500 g as percentage of 1 kg is _______%.

PRACTICE TIME

1. Express:
(a) 60 kg as a percentage of 180 kg (b) 15 s as a percentage of 90 s
(c) 12 km as a percentage of 108 km (d) 150 litres as a percentage of 750 litres
2. What percentage of 80 is 16?

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