Diagonal of a rectangle — Mensuration Aptitude Question
Diagonal of a rectangle: A rectangle measures 24 cm by 7 cm. What is the length of its diagonal? Answer and worked solution on CodeKairo.
- Topic: Mensuration
- Section: Quantitative Aptitude
- Difficulty: Easy
- Time target: 50 seconds
Question
A rectangle measures 24 cm by 7 cm. What is the length of its diagonal?
Options
- 23 cm
- 25 cm
- 27 cm
- 31 cm
Show the answer and the worked solution
Correct answer: B. 25 cm
Worked solution
- Diagonal = √(24² + 7²) = √(576 + 49) = √625 = 25 cm.
Answer: 25 cm.
The idea
7-24-25 is a Pythagorean triple worth memorising alongside 3-4-5, 5-12-13 and 8-15-17.
Shortcut. The diagonal must exceed 24 but fall short of 24 + 7 = 31; 25² = 625 = 576 + 49 confirms 25 cm.
Common trap. "31 cm" — adding the two sides, 24 + 7, as if the diagonal were a walk round two edges.