Question

(ii) The surface area of a cuboid 15 cm broad and 10 cm high is 1300 cm. Find its length.
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Answer 1

TSA of cuboid = 2(lb+bh+hl)

1300 = 2(l×15+15×10+10×l)

1300= (2l× 30+150+10l)

1300=(60l +150+10l)

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Answer 2

Answer:

length = 20cm

Step-by-step explanation:

Given:-

Breadth = 15cm

Height = 10cm

To Find :-

Length = x cm

Solution :-

Surface Area = 1300cm

Total Surface Area of Cuboid = 2(lb+bh+lh)

1300 cm^2 = 2(15x + 150 + 10x)

1300cm^2 = 2(25x + 150)

1300cm^2 = 50x + 300

1300 - 300 = 50x

1000 = 50x

x = 1000/50

x = 20