TASK DEFINITION: In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
PROBLEM: Problem: the unit digit in the product ( 891 * 781 * 912 * 463 ) is : 
Options: a ) 2 , b ) 5 , c ) 6 , d ) 8 , e ) 10

SOLUTION: c

PROBLEM: Problem: a is the hundreds digit of the 3 digit integer x , b is the tens digit of x , and c is the units digit of x . 4 a = 2 b = c , and a > 0 . what is the difference between the two greatest possible values of x ? tip : dont stop till you have exhausted all answer choices to arrive at the correct one . 
Options: a ) 124 , b ) 297 , c ) 394 , d ) 421 , e ) 842

SOLUTION: a

PROBLEM: Problem: ram - leela has $ 100 in her piggy bank . how much will she have in her bank 52 weeks from now if she puts $ 1 in the bank next week , $ 2 two weeks from now , $ 3 3 weeks from now , and continues to increase the amount that she puts in by $ 1 each week ? 
Options: a ) 1478 , b ) 1578 , c ) 1678 , d ) 1778 , e ) 1798

SOLUTION:
a