A store sells batteries in packets of 6 or 10. It has a stock of 25 packets containing a total of 186 batteries. How many of these are 10-battery packets?

Question

bahrom7893 · Answer

So suppose you have x packets of 6 and y packets of 10. The total number of batteries would be:
6*x + 10*y = 186

bahrom7893 · Answer

In total, you have 25 packets, so the sum of all the packets containing 6 and 10 batteries is:
x+y=25

kc_kennylau · Answer

And we don't usually write the asterisk (*) if it's not necessary, so it'd be 6x+10y=186

bahrom7893 · Answer

Solve the system:
6x+10y=186
x+y=25

y will be the number of 10-battery packets