GMATprep DS

[sochatte]

Is the hundredth digit of decimal d greater than 5?

1). The tenth digit of 10d is 7

2). The thousandth digit of d/10 is 7



could someone ecplain.....

[gabriel]

Is the hundredth digit of decimal d greater than 5?

1). The tenth digit of 10d is 7

2). The thousandth digit of d/10 is 7



could someone ecplain.....

Let the decimal d be a.xyz .. so basically the question is, is y is greater than 5.

1.) 10d = ax.yz, the tenth digit of 10d is y and it equal to 7 which is > 5, so sufficient

2.)d/10 = 0.axyz, the thousand digit of d/10 is y and is equal to 7 which is > 5, so sufficient

Hence the answer is D