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Question
The perimeters of two similar triangles are 25 cm and 15 cm respectively. If one side of first triangle is 9 cm, what is the corresponding side of the other triangle?
Solution
Assume ABC and PQR to be 2 triangles
We have,
ΔABC ~ ΔPQR
Perimeter of Δ ABC = 25 cm
Perimeter of Δ PQR = 15 cm
AB = 9 cm
PQ = ?
Since, ΔABC ~ ΔPQR
Then, ratio of perimeter of triangles = ratio of corresponding sides
`rArr25/12="AB"/"PQ"`
`rArr25/15=9/"PQ"`
`rArr"PQ"=(15xx9)/25=5.4` cm
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