Question discussion

70% of a number is equal to four-fifth of another number. If the difference between the two numbers is 100, what is the bigger number ?

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70% of a number is equal to four-fifth of another number. If the difference between the two numbers is 100, what is the bigger number ?
  • A700
  • B750
  • C800
  • DCannot be determined
Answer not set
0
CCommunity
Solution
Let the two numbers be X and Y.

So, 70%*X = 4/5*Y = 80%*Y

Therefore, 7X = 8Y
It also given that X-Y =100.

Hence, 7X-7Y = 700. But 7X=8Y
Therefore, 8Y-7Y = 700 or Y=700

Hence, the bigger number equals Y+100 = 800
0
CCommunity
Solution
Let the two numbers be X and Y.

So, 70%*X = 4/5*Y = 80%*Y

Therefore, 7X = 8Y
It also given that X-Y =100.

Hence, 7X-7Y = 700. But 7X=8Y
Therefore, 8Y-7Y = 700 or Y=700

Hence, the bigger number equals Y+100 = 800