Bunuel
On June 1, Mary paid Omar $360 for rent and utilities for the month of June. Mary moved out early, and Omar refunded the money she paid for utilities, but not for rent, for the days in June after she moved out. How many dollars did Omar refund to Mary?
(1) Mary moved out on June 24.
(2) The amount Mary paid for utilities was less than 1/5 the amount Mary paid for rent.
NEW question from GMAT® Official Guide 2019
(DS08420)
Solution:
We need to determine the amount of money, in dollars, Omar refunded to Mary.
Statement One Alone:Since Mary moved out on June 24, she should be refunded for the 6 remaining unused days of June in utilities, i.e., 6/30 = 1/5 of June’s utilities she has paid. However, since we only know the total amount Mary paid for rent and utilities, but not the actual amount of either expense, we can’t determine the amount of the refund. Statement one alone is not sufficient.
Statement Two Alone:With statement two, since we still can’t determine the actual amount of either expense, we can’t determine the amount of the refund. Statement two is not sufficient.
Statements One and Two Together:Even with the two statements, we still can’t determine the actual amount of each of the two expenses, so we can’t determine the amount of the refund. For example, if the utilities were $50 and the rent was $310 (notice that $50 is less than 1/5 of $310), then the refund should be 1/5 x 50 = $10. However, if the utilities were $40 and the rent was $320 (notice that $40 is less than 1/5 of $320), then the refund should be 1/5 x 40 = $8. Both statements together are not sufficient.
Answer: E