Below given is the Table showing Age-wise Ownership of mobiles:

If 1 crore mobiles were sold last year, how many LG sets were sold?

Let say,

The number mobiles sold in last year of the brands LG, SAMSUNG, NOKIA, SONY, MICRO-MAX be A, B, C, D, and E respectively.

Given that A+B+C+D+E = 1 crore.

Out of these 1 crore mobiles, the number of mobile sets of LG sold  are 15% of A = $$\frac{15}{100}\times A$$.

But from the given data, the values of A, B, C, D, and E cannot be found out.

So the number of LG sets sold last year cannot be determined.

Note that the 15% does not represent the percentage of LG mobiles among the ones that are 1 yr old, but the percentage of 1 yr old mobiles among LG mobiles.