Answer:
2/15
Explanation:
Fractions can be found by dividing the part by the whole.
part/whole
In this problem, the part is the limestone portion of the wall and the whole is the total width of the wall.
limestone/total
16 inches are concrete, 10 inches are brick and 4 inches are limestone. The total width is 30 inches.
limestone = 4
total = 30
4/30
This fraction can be simplified. Both the numerator and denominator can be evenly divided by 2.
(4/2) / (30/2)
2/ (30/2)
2/15
This fraction cannot be simplified further, therefore it is our answer.
2/15 of the wall is limestone.