TCS
Company
Numerical Ability
Area and Volume
Arun makes a popular brand of ice-cream in a rectangular shaped bar 6 cm long, 5 cm wide and 2 cm thick. To cut costs, the company had decided to reduce the volume of the bar by 19%. The thickness will remain the same, but the length and width will be decreased by the same percentage. The new width will be
Read Solution (Total 8)
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- volume v=l*b*t
new volume is 81% of old v.
therefore new vol = 81%(v)=l'*b'*t
=> 81% (l*b*t) = l'*b'*t
=> 81% (l*b) = l' * b'
since the change in new l and b is the same. hence consider change to be x.
=> 81% (l*b) = xl*xb
81%=x^2
x=9%.
9% change in 5cm width is 0.45
therefore new width is 5-0.45=4.55cm - 11 years agoHelpfull: Yes(33) No(4)
- let d width decrease by 10% and length by 10% too..
den total volume degradation will be as thickness is same..
-10 -10 +10*10/100=-19%
thus new width will be 0.9*5 = 4.5cm
- 11 years agoHelpfull: Yes(11) No(4)
- since volume decrease by 19%
so,new vol=60-(60*19)/100=48.6
let length decrease by x%
so,now(6-6x/100)*(5-5x/100)*2=48.6
solving this we get two values of x i.e. x=190,10
so,190 can not be solution so reduired is 10%.
so,new width is 5-5*10/100=4.5.
4.5 is the new width. - 11 years agoHelpfull: Yes(10) No(1)
- 4.05 cm is the ans
- 11 years agoHelpfull: Yes(7) No(5)
- Volume =l×b×h = 6×5×2 = 60 cm3
Now volume is reduced by 19%.
Therefore, new volume = (100−19)100×60=48.6
Now, thickness remains same and let length and breadth be reduced to x%
so, new volume: (x100×6)(x100×5)2=48.6
Solving we get x =90
thus length and width is reduced by 10%
New width = 5-(10% of 5)=4.5 - 10 years agoHelpfull: Yes(6) No(1)
- v=60
new vol=48.6
48.6=l*b*w=x^2*2
x^2=24.3
x=4.92 - 11 years agoHelpfull: Yes(5) No(23)
- but answer is 8.1cm
- 8 years agoHelpfull: Yes(0) No(1)
- initial volume =5*4*3=60
now let w and l is decreased by x% where thickness remains same(2cm)
then
2 * (100-x)%of w * (100-x)%of l=81% of 60
2*(100-x)^2/100 *5*6=(81/100)*60
x=91%
hence
new width is 91%of 5
= 4.55 - 6 years agoHelpfull: Yes(0) No(0)
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