Question

An open box of length 1.5 m breadth and height 1m is to be make for use on a trolley How much sheet metal Will be required to make this? The inside is to the cube is to be painted at a rate OF 150 Paise er sq.m How much Will it cost to paint the box​

Answer 1

$\huge\mathrm\blue{✿Solution:-}$

☞ $\mathrm{Length\:of\:the\:box,l\:=\:1.5\:m}$

☞ $\mathrm{Breadth\:of\:the\:box,b\:=\:1\:m}$

☞ $\mathrm{Height\:of\:the\:box,h\:=\:1\:m}$

Surface area of open box = Total surface area of the box - Area of the top

$\Rightarrow{ }$ $\mathrm{2(l×b+b×h+l×h)-l×b}$

$\Rightarrow{ }$ $\mathrm{2(1.5×1+1×1+1.5×1)-1.5×1}$

$\Rightarrow{ }$ $\mathrm{2(1.5+1+1.5)-1.5}$

$\Rightarrow{ }$ $\mathrm{2×4-1.5}$

$\Rightarrow{ }$ $\mathrm{8-1.5}$

$\Rightarrow{ }$ 6.5 $\normalsize\mathrm{m}^2$

$\rule{200pt}{2pt}$

Hence, 6.5 $\normalsize\mathrm{m}^2$of the sheet will be required to make the open box .

$\rule{200pt}{2pt}$

Now , it is given that inside the of the open box is to be painted .

Surface Area of the open box to be painted = 6.5 $\normalsize\mathrm{m}^2$

Now, the Cost of the painting of 1 $\normalsize\mathrm{m}^2$of area is 150 paise

cost of painting of 6.5 $\normalsize\mathrm{m}^2$= 6.5×150 = 975 paise = 9.75 Rupees