Page 285 - Math Smart - 7

Express 180 cm as a percentage of 3 m.
Solution
3 m = 300 cm
X
^ 100% = 60%
180 cm is 60% of 3 m.

Example 11

Em scored 62 marks out of a maximum of 75 marks in a test. Express Em's score as
a percentage of the full marks. Round your answer to 1 decimal place.

Solution
X 100% = 82.66...%
= 82.7% (rounded to 1 decimal place)
Em's score was about 82.7% of the full marks (rounded to 1 decimal place).

Check My
Understanding

O Express the first quantity as a percentage of the second quantity,
a) 7 out of 10 b) 42 out of 50 c) 2 out of 3 d) 16 out of 3 000
O Express the first quantity as a percentage of the second quantity,

a) 40 min, 50 min b) 45 min, 1 h c) 27 s, 3.6 min
d) 3 mth, 1 yr e) $2.40, 72 c f) 1 kg, 800 g
Q Draw 8 cylinders.
a) Label 5 of them'C for cola.
b) Write down the percentage of cans that are cola.
c) Write down the percentage of cans that are not cola. Label them 'O' for orange.
d) Write down the fraction of cans that are orange.
O There are 90 teachers in a school. 40 of them are male. Find the percentage of

a) male teachers and
b) female teachers in the school.

@ List the numbers 1 to 10.
a) What percentage of these numbers are odd numbers?
b) What percentage are even numbers?
c) What percentage are numbers greater than 7?
d) What percentage are numbers less than 5?
e) What percentage are prime numbers?