A university offers its students on-campus housing in university-owned apartments. The majority of the apartments are unfurnished, but the university does offer a small number of fully furnished apartments for an extra charge. The table lists the number of each type of apartment that the university offers as well as the monthly rent that the university charged for those apartments in each of two years.
| Unit Type | Furnished? | # Units | Y1 Monthly Rent | Y2 Monthly Rent |
| Studio | N | 215 | 705 | 747 |
| Studio | Y | 20 | 730 | 752 |
| 1 Bedroom | N | 2500 | 766 | 771 |
| 1 Bedroom | Y | 10 | 867 | 893 |
| 2 Bedroom | N | 4000 | 1045 | 1039 |
| 2 Bedroom | Y | 100 | 1112 | 1172 |
For each of the following unit types, select Yes if the university charged greater than 10 percent more for furnished units of that type than they charged for the unfurnished units of that type in both of the years depicted in the table. Otherwise, select No.To determine whether the university charged more than 10 percent more for furnished units of each type, we could use the calculator to divide the furnished unit rent for each type by the unfurnished rent of each type and see whether the result is greater than 1.10.
However, it's probably faster just to move the decimal point one digit to the left in the case of the rent for a unfurnished unit of each type, round to the nearest greater integer, add to the rent for the unfurnished unit, and see whether the result is greater than the rent for the corresponding furnished unit.
After all, it may turn out that we don't even have to complete the addition to see that the the sum must be greater than the rent for a furnished unit. If one of the sums is close to the rent for the furnished type, we can do the addition and compare more carefully.
Studio Y1: 705 + 71 > 730
Y2: 747 + 75 > 752
Select
No.1 BedroomY1: 766 + 77 < 867
Y2: 771 + 72 < 893
Select
Yes. 2 BedroomY1: 1045 + 105 > 112
Y2: 1039 + 104 < 1172
Select
No.It turns out that, in every case, it's pretty easy to see whether the sum is greater or less than the rent for the furnished type. So, as long as we don't make any careless errors, we can get this one correct pretty quickly without the calculator.Correct answer: No,
Yes,
No