Question

the cost of making a wooden frame for apicture at ₹8 per centimetre is ₹240.if the Length of the picture is 8cm,find its width.

Answer 1

perimeter = 30 cm
2(l+b)=30 cm
2(8+b)=30
16+2b= 30
b= 7cm


answer is 7 cm

Answer 2

❄️ Solution :

Cost of the picture = ₹240

Rate of framing = ₹8 per cm

Perimeter of the photographer

$\\ = \sf \: \frac{ Total~~cost~(₹) }{Rate~(₹/cm)} \\ \\ = \sf \: \frac{240}{8} \: = \purple{30 \: cm}$

Let the width of picture be x.

Perimeter = 2(L + B) = 2(8 + x) Length of the picture = as 8 cm

→ 30 = 16 + 2x

→ 30 - 16 = 2x

→ 14 = 2x

→ x = 14/2

→ x = 7 cm

By trial and error method:

→ 2x + 16

→ 2 × 7 + 16

→ 14 + 16

→ 30

Therefore, width of the picture is 7 cm.