Page 169 - ICSE Math 4

Example 14: Write the temperature shown on the following Celsius thermometers.

(a)

0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100°

(b)

0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100°

Solu on: (a) 25°C (b) 52°C

Now let’s learn to convert temperature in °C to temperature in °F and vice versa.
Converting Temperature from °C to °F

To convert temperature from °C to °F, we use the following formula. 9 × °C + 32 = °F
5
Example 15: Convert 25°C to °F.

9
Solu on: 9 × °C + 32 = × 25 + 32
5 5
Step 1: Mul ply 25 by 9. Step 2: Divide the product by 5.
25 × 9 = 225 225  5 = 45

Step 3: Add 32 to the quo ent obtained.
45  32 = 77
So, 25°C = 77°F.

Converting Temperature from °F to °C

5
To convert temperature from °F to °C, we use the following formula. × (°F – 32) = °C
9
Example 16: Convert 113°F to °C.
5
Solu on: 5 × (°F – 32) = × (113 – 32)
9 9
Step 1: Subtract 32 from 113. Step 2: Mul ply 81 by 5.

113 – 32 = 81 81 × 5 = 405
Step 3: Divide the product by 9.
405  9 = 45

So, 113°F = 45°C.

Exercise 12.6

1. Write the temperature shown on the given Celcius thermometes.

(a)

0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100°
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