Page 176 - Start Up Mathematics_8 (Non CCE)

AT a Glance

1. Percent means “in one hundred” or “per hundred”.
2. By a certain percent means that many hundredths.

3. A fraction with its denominator as 100 is equal to the percent of that numerator.
4. To convert a fraction into percent, multiply the fraction by 100 and put the percent sign (%).
5. To convert percent into fraction, divide the percent by 100 and remove the percent sign (%).
6. To convert percent into ratio, remove the percent sign and form a ratio with the remaining number as the
first term and 100 as the second term.
7. To convert ratio into percent, write the ratio as a fraction and multiply by 100. Then place the percent
sign (%).
8. To convert percent into decimal, change the percent into a fraction with denominator 100 and express in
the decimal form.
9. To convert a decimal into percent, shift the decimal 2 places to the right and put the percent sign (%).
px¥ px
10. p% of x = =
100 100
Ê Increase ˆ Ê Decrease ˆ
11. Increase% = Á Original value ¥ 100 %, Decrease% = Á Original value ¥ 100 %
˜
˜
¯
Ë
¯
Ë
Review Exercises

Multiple ChoiCe Questions
1
1. The decimal equivalent of 5 % is:
2
(a) 0.55 (b) 0.055 (c) 5.5 (d) 0.0055
2. The ratio 6 : 25 is equal to:
(a) 20% (b) 25% (c) 22% (d) 24%
3. If x% of 50 is 2, then the value of x is:
(a) 3 (b) 4 (c) 2 (d) 5
4. Sonam saves 15% of her income per month. If she saves ` 450 per month, her income is:
(a) ` 4,000 (b) ` 2,500 (c) ` 3,000 (d) ` 3,500
5. If 17% of a certain number of mangoes is equal to 1,360, the number of mangoes is:
(a) 8,000 (b) 6,000 (c) 8,500 (d) 7,000
1
6. The duty on goods worth ` 6,200 at 2 % is:
2
(a) ` 125 (b) ` 135 (c) ` 145 (d) ` 155

solve Mentally

Fill in the Blanks

1. To convert ratio into percent, convert the ratio into ___________, ___________ the fraction with 100
and place the percent sign.

2. ___________% of ` 900 is equal to ` 270.

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