Question

(05.06)A chocolate bar measures 30 mm wide, 70 mm long, and four and one over two mm high. Will’s Wrapping Company is making a wrapper to cover the chocolate bar. Use the correct net and determine how much paper will be needed to make the wrapper.

Answer 1

`5100mm^(2)`

Explanation:

Given : A chocolate bar measures 30 mm wide, 70 mm long, and four and one over two mm high

To Find : how much paper will be needed to make the wrapper.

Solution :

Length of chocolate bar = 70 mm

Width of chocolate bar = 30 mm

Height of chocolate bar =
`4(1)/(2) =(9)/(2) =4.5 mm`

Since chocolate bar in in the shape of cuboid

Total surface area of cuboid : 2(length*width+width*height+height*length)

Thus the wrapper required to wrap chocolate = 2(70*30+30*4.5+4.5*70)

= 2100+135+315

= 2(2550)

= 5100 square mm

Hence
`5100mm^(2)` paper will be needed to make the wrapper.

Answer 2

we know that

[surface area]=2*[area of the base]+[perimeter of the base]*height
area of the base=30*70-----> 2100 mm²

perimeter of the base=2*(30+70)-----> 200 mm
height=4 1/2 mm-----> (4*2+1)/2-----> 9/2 mm
[surface area]=2*[2100]+[200]*9/2-----> 5100 mm²

the answer is
5100 mm²