UNITARY METHOD IN PERCENTAGE

Problem 1 :

Find 100% if 30% is 48

Solution :

30% is 48 

30% = 48

1% = 48/30

100% = 100 x (48/30)

= 160

So 100% is 160.

Problem 2 :

Find 100% if 16% is 2.56 L

Solution :

16% is 2.56 L

16% = 2.56 L

1% = 2.56/16

1% = 0.16

100% = 100(0.16)

100% = 16 L

Problem 3 :

Find 100% if 13% is 416 kg

Solution :

13% is 416 kg

13% = 416 kg

1% = 416/13

1% = 32

100% = 100 x 32

100% = 3200 kg

Problem 4 :

Find 100% if 87% is 1131 kg

Solution :

87% is 1131 kg

87% = 1131 kg

1% = 1131/87

1% = 13

100% = 100 x 13

100% = 1300 kg

Problem 5 :

Find 100% if 22% is 77 L

Solution :

22% is 77 L

22% = 77 L

1% = 77/22

1% = 3.5

100% = 100 x 3.5

100% = 350 L

Problem 6 :

Find 100% if 36% is 252 kg

Solution :

36% is 252 kg

36% = 252 kg

1% = 252/36

1% = 7

100% = 100(7)

100% = 700 kg

Problem 7 :

Find 40% if 9% is 117

Solution :

40% if 9% is 117

9% = 117

1% = 117/9

1% = 13

40% = 40(13)

40% = 520

Problem 8 :

Find 6% if 48% is 630

Solution :

6% if 48% is 630

48% = 630

1% = 630/48

1% = 13.125

6% = 6(13.125)

6% = 78.75

Problem 9 :

Find 90% if 6% is 14 kg

Solution :

90% if 6% is 14 kg

6% = 14

1% = 14/6

90% = 90(14/6)

90% = 210 kg

Problem 10 :

Find 72% if 6% is 96 kg

Solution :

72% if 6% is 96 kg

6% = 96

1% = 96/6

1% = 16

72% = 72(16)

72% = 1152 kg

Problem 10 :

The width of a rectangular room is 80% of its length. What is the area of the room ?

Solution :

Length = 15 ft

Width = 80% of 15

= 0.80(15)

= 12

Area of rectangle = length x width

= 15 x 12

= 180 square ft

Problem 11 :

You win an online auction for concert tickets. Your winning bid is 60% of your maximum bid. How much more were you willing to pay for the tickets than you actually paid?

a)  $72    b)  $80     c) $120    d) $200

Solution :

Winning bid = 120

= 60% of 120

= 0.60(120)

= 72

Option a is correct.

Problem 12 :

You raise $420 during a fundraising event. The amount of money that you raise is 120% of your goal. How much more did you raise than your goal?

Solution :

Let x be the amount of goal and it is 100%

The amount that you raise = $420

120% of x = 420

1.20 x = 420

x = 420/1.20

x = 350

So, the target is $350.

Problem 13 :

A shirt is on sale for 60% of the original price. The original price is $28 more than the sale price. What was the original price?

Solution :

Let x be the original price

Sale price = 60% of origianl price

= 60% of x

= 0.60x

Original price = 28 + 0.60x

x = 28 + 0.60x 

x - 0.60x = 28

0.40x = 28

x = 28/0.40

x = 70

So, the original price is $70

Problem 14 :

You have a meal at a restaurant. The sales tax is 8%. You leave a tip for the waitress that is 20% of the pretax price. You spend a total of $23.04. What is the pretax price of the meal?

Solution :

Sales tax = 8%

Let x be the sale price before tax.

Tip = 20% of x

Total amount spent = 23.04

x + 8% of x + 20% of x = 23.04

x + 0.08x + 0.2x = 23.04

1.28x = 23.04

x = 23.04/1.28

x = 18

Problem 15 :

34% of students at a school using public transport. If 204 students use public transport, how many students attend the school ?

Solution :

Total number of students = x

Number of students who use public transoport = 204

34% of x = 204

0.34x = 204

x = 204/0.34

x = 600

So, the total number students attend the school is 600.

Problem 15 :

Darko scored 81% for a test. If his acutal score was 121  1/2, what was the maximum possible mark for the test ?

Solution :

Let x be the maximum possible mark.

81% of x = 121  1/2

81% of x = 121.5

0.81x = 121.5

x = 121.5/0.81

x = 150

So, the total score is 150.