Two numbers are less than a third number by 30% and 37 % respectively. How much percent is the second number less than the first?
a) 10 % b) 7 % c) 4 % d) 3 %
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Difficult Math Question #34 - Arithmetic
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ajith
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Two numbers are less than a third number by 30% and 37 % respectively. How much percent is the second number less than the first?
a) 10 % b) 7 % c) 4 % d) 3 %
A is the answer ..
say the original no is X
first no: is .7X
second no: is .63X
it is (.7-.63) X/.7 =.1 =10%
a) 10 % b) 7 % c) 4 % d) 3 %
A is the answer ..
say the original no is X
first no: is .7X
second no: is .63X
it is (.7-.63) X/.7 =.1 =10%
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rajs.kumar
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navdeepbajwa
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I can't understand this part
diff in %= (.7 - .63)/.7 * 100
why we have to divide by 0.7 why can't it be difference * 100 = 7%
thanks
diff in %= (.7 - .63)/.7 * 100
why we have to divide by 0.7 why can't it be difference * 100 = 7%
thanks
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regor60
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Keep track of the base.navdeepbajwa wrote:I can't understand this part
diff in %= (.7 - .63)/.7 * 100
why we have to divide by 0.7 why can't it be difference * 100 = 7%
thanks
The difference of 7% is referenced to the "third" number. 10% is the difference referenced to the "first" number, which itself is 70% of the "third" number. The question is asking for the difference referenced to the "first" number.
