中等ICT-EXAM-014
A pupil works out 200 × 100 × 24 and writes 480 000. The question asked for the size in bytes. What is still missing?
A. Divide by 8, because 480 000 is a number of bits, and state the unit bytes.✓ 答案
B. Multiply by 8 again.
C. Nothing, because 480 000 is already in megabytes.
D. Remove the colour depth, because it is not part of a bitmap size.
解說
Width × height × colour depth gives bits. There are 8 bits in a byte, so the size is 480 000 ÷ 8 = 60 000 bytes.