Jasper Eng's answer to Koh Zekai's Secondary 3 A Maths Singapore question.
done
{{ upvoteCount }} Upvotes
clear
{{ downvoteCount * -1 }} Downvotes
For similarity and Congruency, the ratios are fixed,
Given radii (ratio of length)
= 1:3
A) base area ratio (square the ratio)
= 1 * 1 : 3 * 3
= 1 : 9 //
B) volume ratio (cube the ratio)
= 1 * 1 * 1 : 3 * 3 * 3
= 1 : 27 //
C) from (a), the ratio is 1:9
:. Area of smaller hemi
= 450 / 9
= 50cm^2 //
Given radii (ratio of length)
= 1:3
A) base area ratio (square the ratio)
= 1 * 1 : 3 * 3
= 1 : 9 //
B) volume ratio (cube the ratio)
= 1 * 1 * 1 : 3 * 3 * 3
= 1 : 27 //
C) from (a), the ratio is 1:9
:. Area of smaller hemi
= 450 / 9
= 50cm^2 //
Date Posted:
3 years ago
360 Tutoring Program