Measurement, time & conversions · Topic 13 of 15

Temperature: Fahrenheit ↔ Celsius

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Math · temperature

°F = 9/5 °C + 32 and °C = 5/9 (°F − 32); anchor answers to 0/32, 37/98.6 and 100/212.

01 · °C → °F°F = 9/5 × °C + 32

02 · °F → °C°C = 5/9 × (°F − 32)

03 · MemorizeBody temp 37 °C = 98.6 °F

°F → °C: do the subtraction in parentheses first

°C → °F: multiply first, add 32 last

°C → °F: multiply by 9/5, then add 32 must know

°F → °C: subtract 32, then multiply by 5/9 must know

Water freezes at 0 °C = 32 °F and boils at 100 °C = 212 °F must know

Normal body temperature: 37 °C = 98.6 °F must know

9/5 = 1.8: °F = 1.8 °C + 32; °C = (°F − 32) ÷ 1.8

39 °C: 1.8 × 39 = 70.2; 70.2 + 32 = 102.2 °F

77 °F: 77 − 32 = 45; 5/9 × 45 = 25 °C

101.3 °F: 101.3 − 32 = 69.3; 5/9 × 69.3 = 38.5 °C

Commonly confused

Subtract 32 before multiplying: 212 °F = 100 °C, not 85.8 °C

Don't swap 9/5 and 5/9 — above freezing, °F is the bigger number

Show 3 more facts

1 Celsius degree = 1.8 Fahrenheit degrees (100 C° span = 180 F°)

−40 °C = −40 °F (the one point where the scales meet)

Kelvin (water freezes at 273.15 K) is a Chemistry topic

Pearl

To Fahrenheit, add 32 last; to Celsius, take 32 away first.

Practice this topic, then test the whole section.

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