Question
Find the third proportion to the following :
3 and 15
3 and 15
✓
Answer
Let x be the third proportion
3 : 15 :: 15 : x
⇒ 3 × x- 15 x 15
⇒ 3 x = 225
⇒ x = 75
The third proportion is 75.
3 : 15 :: 15 : x
⇒ 3 × x- 15 x 15
⇒ 3 x = 225
⇒ x = 75
The third proportion is 75.
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