A man purchased a box full of pencils at the rate of 7 for Rs. 9 and sold all of them at the rate of 8 for Rs. 11. In this transaction, he gained Rs. 10. How many pencils did the box contain?
115
110
112
114
119
112
Suppose, number of pencils bought = L.C.M. of 7 and 8 = 56.
C.P. of 56 pencils = Rs. (97×56)= Rs. 72.
S.P. of 56 pencils = Rs. (118×56)=Rs.77
Now, Rs. 5 are gained on 56 pencils.
So, Rs. 10 are gained on (565×10)=112 pencils.