44 bags of hardwood, 112 bags of pine bark mulch.
we have two equations. I’ll call hardwood h, and pine bark p.
The number of bags: h + p = 156
The cost of the bags: 4h + 3.75p = 596
Start by solving the first equation for h in terms of p
h = 156 - p
Then substitute that in the other equation for h, and solve for a numerical value of p
4(156-p) + 3.75p = 596
624 -4p + 3.75p = 596
28 = 0.25p
p = 112
Now plug that in to the first equation to get the numerical value of h
h + p = 156
h + 112 = 156
h = 44
Check the math:
4(44) + 3.75(112)
176 + 420 = 596
