question_answer

Observe the given subtraction. \[\frac{\begin{align}   & \,\,\,\,\,5~~(a)~~\,0 \\  & -\text{ (b)}~\,\,7\,\,2 \\ \end{align}}{\,\,\,\,\,2\,\,1\,\,8}\]                      What are the values of (a) and (b)?

A) a = 3, b = 9               

B) a = 6, b = 4   

C)      a = 9,b = 3    

D)      a = 6, b = 6               

Correct Answer: C

Solution :

 5  \[\] 0 - \[\] 7   2 __________  2       1     8             __________ 8 + 2 = 10 \[\to \] is carried to tens place \[\therefore \] (a) = 7 + 1 +  = 9 and (b) = 5- 2 = 3