Question

Last year all refuse collected by Shelbyville city services was incinerated. This incineration generated a large quantity of residual ash. In order to reduce the amount of residual ash Shelbyville generates this year to half of last year's total, the city has revamped its collection program. This year city services will separate for recycling enough refuse to reduce the number of truckloads of refuse to be incinerated to half of last year's number.
Which of the following is required for the revamped collection program to achieve its aim?


(A) This year, no materials that city services could separate for recycling will be incinerated.
(B) Separating recyclable materials from materials to be incinerated will cost Shelbyville less than half what it cost last year to dispose of the residual ash.
(C) Refuse collected by city services will contain a larger proportion of recyclable materials this year than it did last year.
(D) The refuse incinerated this year will generate no more residual ash per truckload incinerated than did the refuse incinerated last year.
(E) The total quantity of refuse collected by Shelbyville city service's this year will be no greater than that collected last year.

Answer 1

Answer:

D) The refuse incinerated this year will generate no more residual ash per truckload incinerated than did the refuse incinerated last year.  IF THE WHOLE POINT OF THE PROGRAM IS TO REDUCE THE AMOUNT OF RESIDUAL ASH, THEN IT IS IMPORTANT TO CHECK IF CUTTING THE TRUCKLOADS OF WASTE BY HALF ACTUALLY CUTS RESIDUAL ASH BY HALF.  

Explanation:

Other options are wrong because:

• A) This year, no materials that city services could separate for recycling will be incinerated.  THE PURPOSE OF THE PROGRAM IS TO REDUCE RESIDUAL ASH TO HALF, AND THAT COULD BE ACHIEVED EVEN IF SOME RECYCLABLE MATERIALS WERE BURNT.
• B) Separating recyclable materials from materials to be incinerated will cost Shelbyville less than half what it cost last year to dispose of the residual ash.  THE QUESTION DOESN'T DEAL WITH THE COSTS OF RECYCLING OR INCINERATION.
• C) Refuse collected by city services will contain a larger proportion of recyclable materials this year than it did last year.  THIS CANNOT BE CONTROLLED BY THE LOCAL GOVERNMENT, SO IT DOESN'T SERVE AS A PARAMETER.
• E) The total quantity of refuse collected by Shelbyville city service's this year will be no greater than that collected last year. THIS CANNOT BE CONTROLLED BY THE LOCAL GOVERNMENT, SO IT DOESN'T SERVE AS A PARAMETER.

Answer 2

Answer:

The correct option is D

Explanation:

Cutting the number of truckloads of refuse in half must reduce the amount of residual ash by half of last year's level. However, if the removal of the recycled refuse does not proportionately reduce the amount of ash, this will not happen.

So, the answer D states a requirement for the collection program to achieve its aim.