Shortcuts in "PERCENTAGE" problems
PERCENTAGES
1. The ratio 5: 4 expressed as a percent equals:
a) 12.5% b) 40% c) 80% d) 125%
Shortcut:
(5/4) x100=125%
2. 3.5 can be expressed in terms of percentage as:
a) 0.35% B) 3.5% c) 35% d) 350%
Shortcut:
3.5 × 100 = 350 %
3. Half of 1 percent written as a decimal is:
a) 0.005 b) 0.05 c) 0.02 d) 0.2
Shortcut:
(1/ 2) % = (0.5 / 100) = 0.005
4. What is 15 percent of Rs. 34 ?
a) Rs.3.40 b) Rs. 3.75 c) Rs.4.50 d) Rs.5.10
Shortcut:
34 x (15 / 100) = (51 / 10) = 5.10
5. 63% of 3 4/7 is:
a) 2.25 b) 2.40 c) 2.50 d) 2.75
Shortcut:
(63 / 100) x 3 4/7
(63 / 100) x (25 / 7) = (225 / 100) = 2.25
6. 88% of 370 + 24% of 210 - ? = 118
a) 256 b) 258 c) 268 d) 358
Shortcut:
88 % of 370 + 24 % of 210 - ? = 118
By the Digital Root Method
7x1+ 6 x 3 -1= x
7+ 8 = x
x = 15
x = 6
From the Option (b)
258 = 2 + 5 + 8 = 15
15 = 1 + 5 = 6
7. 860% of 50 + 50% of 860 = ?
a) 430 b) 516 c) 860 d) 960
Shortcut: I
860% of 50 + 50% of 860
x % of y = y % of x
50 % of 860 + 50 % of 860
= (1 /2) x 860 + (1 / 2) x 860
= 860 (1/2 + 1/2)
= 860.
Shortcut: II
By the Digital Root Method:
5 x 5 + 5 x 5 = 7 + 7 = 14 = 1 + 4 = 5
Ans: 860 = 8 + 6 + 0 = 14 = 1 + 4 = 5
8. 45 % of 750 - 25 % of 480 = ?
a) 216 b) 217.50 c) 236.50 d) 245
Shortcut:
45 % of 750 - 25 % of 480
Digital Root Method:
9 x 3 - 7 x 3 = x
9 - 3 = x
x = 6
From the Option (b)
217. 5 = 15 = 6
9. 40 % of 1640 + ? = 35 % of 980 + 150 % of 850
a) 372 b) 842 c) 962 d) 1052
Shortcut:
40 % of 1640 + x = 35 % of 980 + 150 % of 850
Digital Root Method:
4 × 2 + x = 8 x 8 + 6 x 4
x = 1 + 6 - 8
x = 7 - 8 = 1 + 9
x = 8
From the Option (c) 962
9 + 6 + 2 = 8
10. 218 % of 1674 = ? x 1800
a) 0.5 b) 4 c) 6 d) None
Shortcut: I
(218 / 100) x1674 = ? x 1800
(109 / 50) x (1674 / 1800) = x
x = 2.0274
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