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प्रश्न
A vertical stick of length 6 m casts a shadow 400 cm long on the ground and at the same time a tower casts a shadow 28 m long. Using similarity, find the height of the tower
उत्तर
In ∆ABC and ∆PQR,
∠ABC = ∠PQR = 90° ...(Vertical Stick)
∠ACB = ∠PRQ ...(Same time casts shadow)
∆BCA ~ ∆QRP
`"AB"/"PQ" = "NC"/"QR"`
`6/x = 4/28`
4x = 6 × 28
⇒ x = `(6 xx 28)/4` = 42
Length of the lamp post = 42 m
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