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Question
The corresponding sides of two similar triangles ABC and DEF are BC = 9.1cm and EF = 6.5cm. If the perimeter of ΔDEF is 25cm, find the perimeter of ΔABC.
Solution
It is given that Δ ABC - Δ DEF.
Therefore, their corresponding sides will be proportional.
Also, the ratio of the perimeters of similar triangles is same as the ratio of their corresponding sides.
⇒ `("Perimeter of ΔABC")/("Perimete of ΔDEF")=(BC)/(EF)`
Let the perimeter of ΔABC be X cm Therefore,
`x/25=9.1/6.5`
`⇒x=(9.1xx25)/6.5=35`
Thus, the perimeter of ΔABC is 35 cm.
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