One pack of cake mix is being stirred before being poured into two separate baking trays. The first tray can hold a certain amount of cups of the mix while the other holds 20 cups less than the first. If the total number of cups poured is 500, how many cups of batter does the second tray hold?  Choose the correct choice:
A) 250
B) 260
C) 500
D) 280
E) 240

Rationale: tray one as t 1 and tray two as t 2 . t 2 = t 1 - 20 cups as equation a . t 1 + t 2 = 500 cups in total as equation b . substitute equation a into equation b , resulting in t 1 + ( t 1 - 20 ) = 500 transpose like terms , 2 * t 1 = 500 + 20 ( 2 * t 1 ) / 2 = 520 / 2 t 1 = 260 , thus t 2 is t 1 less 20 cups , which is 240 cups . answer is e .
Answer: E