Medium
At what temperature do the Celsius and Fahrenheit scales show the same numerical value?
Explanation
Explanation
Step 1: The conversion formula is F = (9/5) × C + 32.
Step 2: Let both readings be equal to x. So x = (9/5)x + 32.
Step 3: x − (9/5)x = 32, so −(4/5)x = 32.
Step 4: x = 32 × (−5/4) = −40.
Step 5: Check: (9/5)(−40) + 32 = −72 + 32 = −40 ✓.
Answer: −40°.
PRO TIP
Re-check your working by substituting the answer back into the original question.