Alocal boys club sold 176 bags of mulch and made a total of $520. it sold two types of mulch : hardwood for $3.50 a bag and pine bark for $2.75 a bag. how many bags of each kind of mulch did it sell?

So here is the answer.
We represent h = hardwood and p = pine bark
Here is the equation: h + p = 176
2.75p + 3.50h = 520
Next, p = 176 -h (substitute)
2.75 (176-h) + 3.5h = 520
484 -2.75h + 3.5h = 520
3.5h-2.75h = 520 -484
0.75h = 36 (divide both by 0.75)
h = 48
Therefore, the number of hardwood sold is 48.
h + p = 176
p = 176-48
p= 128
The number of pine bark sold is 128.
Hope this helps.