2000 General Studies, all questions
UPSC Prelims 2000 · General Studies
Question 150: Basic Numeracy
What is the maximum number of pieces of 5 cm × 5 cm × 10 cm cake that can be cut from a big cake of 5 cm × 30 cm × 30 cm size?
a10
b15
c18
d30
AnswerThe answer is (c).
The big cake has volume 5 x 30 x 30 = 4,500 cubic cm and each piece 5 x 5 x 10 = 250 cubic cm, so at most 18 pieces. This is possible: keep the 5 cm thickness, and on the 30 x 30 face cut three strips each 10 cm wide, then six pieces of 5 cm along each strip. That gives 3 x 6 = 18 pieces.
Why each option is right or wrong
- (a) 10 pieces is fewer than the 18 that can be cut.
- (b) 15 pieces is fewer than the 18 that can be cut.
- (c) Right: 4,500 / 250 = 18, and the cutting plan achieves it.
- (d) 30 pieces would need 7,500 cubic cm, more than the cake holds.
Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2000, General Studies. UPSC's own paper isn't online; the words are from a published compilation. The paper on upsc.gov.in.