Question

A rectangle has a perimeter measuring 64cm. The length is 4cm more than 3 times the breadth,then the length of the rectangle is, *

A) 20cm
B) 25cm
C) 30cm
D) 35cm​

Answer 1

$\huge{ \boxed{ \boxed{ \bold \red{25 \: cm}}}}$

Step by step

Let the breadth of the rectangle be x cm.

Length is 4 cm more than 3 times the breadth.

Length = (3x + 4) cm

We know,

${\boxed{\sf{Perimeter\:of\: rectangle=2(Length+Breadth)}}}$

Perimeter = 2(3x+4+x) cm

→ Perimeter = 2(4x+4) cm

→ Perimeter = 8(x+1) cm

★ According to the question,

$\sf{\:\:\:\:\:8(x+1)=64}$

$\implies\sf{x+1=\frac{64}{8}}$

$\implies\sf{x+1=8} \\ \implies\sf{x=8-1} \\ \implies\sf{x=7}$

Breadth = 7 cm.

Length = (3 × 7 + 4 ) cm

→ Length = 25 cm