Answer:
37 - 56 lb / ft3
0.6 - 0.9 103 kg / m3
Step-by-step explanation:
The density or hardness of wood varies by species, and the value is necessary to approximate the weight of lumber by volume. In this table, the density of different species of wood is expressed as weight in pounds per cubic foot and kilograms per cubic meter. The density will vary based on the moisture content of the wood.
A + s = 456........a = 456 - s
3.5a + s = 1131
3.5(456 - s) + s = 1131
1596 - 3.5s + s = 1131
-3.5s + s = 1131 - 1596
-2.5s = - 465
s = -465/-2.5
s = 186 <====== student tickets sold
a + s = 456
a + 186 = 456
a = 456 - 186
a = 270 <==== adult tickets sold
