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Maths Puzzle
Numerical Ability
Percentage
A number is mistakenly divided by 5 instead of being multiplied by 5. Find the percentage change in the result due t this mistake.
(a)96% (b)95% (c)2400% (d)200%
Read Solution (Total 6)
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- lets take a number 20
20/5 = 4
20*5 = 100
diff = 100 - 4 = 96 % - 14 years agoHelpfull: Yes(8) No(7)
- let assume it is x
then after dividing by 5 number will x/5
and after multiplying by 5 number will 5x.
so our correct value is 5x apply formula
Percentage Error = ((True value - False Value)*100)/True Value
= ((5x-x/5)*100)/5x
= (24x*100)/25x
= 96 - 14 years agoHelpfull: Yes(5) No(3)
- let the no be y ,
so after multiplied by 5 the no will be 5y but instead it is divided so the no is y/5 .
so the difference is 5y-y/5= 24y/25
therefore %age error is 24y/25 / y X 100% = 96%.
so ans (a) 96 % - 14 years agoHelpfull: Yes(3) No(3)
- let no be 1
divided by 5 ->.2
multiplied by 5->5
change in result ->4.8
%-age->(4.8/5)*100=96% - 14 years agoHelpfull: Yes(2) No(2)
- lets take number 100
100/5=20
100*5=500
then net error-> 500-20=480
so (480/20)*100
ans = 2400/% - 11 years agoHelpfull: Yes(0) No(4)
- 96%
((5x-x/5)/5x)*100=96% - 9 years agoHelpfull: Yes(0) No(0)
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