If this week there were 3,750 more internet addicts than last week, by what percent has the number of internet addicts increased from last week to this week?
(1) There are 4 times as many internet addicts this week as last week.
(2) The number of internet addicts this week is 5000.
The OA is D.
Please, can any expert explain this DS question for me? I have many difficulties to understand why that is the correct answer. Thanks.
If this week there were 3,750 more internet addicts...
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Say last week, the number of connections = x, and this week, the number of connections = y.AAPL wrote:If this week there were 3,750 more internet addicts than last week, by what percent has the number of internet addicts increased from last week to this week?
(1) There are 4 times as many internet addicts this week as last week.
(2) The number of internet addicts this week is 5000.
The OA is D.
Please, can any expert explain this DS question for me? I have many difficulties to understand why that is the correct answer. Thanks.
We are given that y - x = 3750.
We have to get the value of [(y - x)/x]*100%.
(1) There are 4 times as many internet addicts this week as last week.
=> y = 4x
Thus, [(y - x)/x]*100% = [(4x - x)/x]*100% = [3x/x]*100% = 300%. Sufficient
(2) The number of internet addicts this week is 5000.
=> y = 5000.
Thus, from y - x = 3750, we get that x = 5000 - 3750 = 1250.
Thus, [(y - x)/x]*100% = [3750/1250]*100% = 300%. Sufficient
The correct answer: D
Hope this helps!
-Jay
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