A cuboidal ice-cream bar have a length, breadth and thickness of 3 cm,5 cm and 2 cm respectively. Suppose both length and breadth decrease by the same percentage and the thickness remains the same. As a result, volume is reduced by 19%. What is the now breath?

ans:4.7
l*b*w=30
19% of it is 5.7
30-5.7=24.3
new volume=(3-x)*(5-x)*(2)=24.3
x=0.3
new b=5-0.3=4.7
10 years agoHelpfull: Yes(18) No(22)
let x be percentage of decrease of length
[3-((x/100)*3)]*[5-((x/100)*5)]*2=[30-((19/100)*30)]
or x^2-200x=1900=0
therefore x=10,19
checking we get x=10
therefore breadth=[5-((10/100)*5)]=5-.5=4.5
10 years agoHelpfull: Yes(7) No(0)
answer is 4.5.
if breadth is decreased by 10% then volume is reduced to 19%.
10 years agoHelpfull: Yes(5) No(0)
(L-Lx/100*b-bx/100*t)/Lbt=81/100
(1-x/100)(1-x/100)=81/100
(1-x/100)^2=(9/10)^2
(1-x/100)^2= (1-1/10)^2
x=1%
1%0f 5
10 years agoHelpfull: Yes(1) No(1)
answer is 4.7
when the volume is reduced by 19%
10 years agoHelpfull: Yes(0) No(4)

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