Question

If a 40-foot tree casts a 12-foot shadow, find the length of the shadow cast by a 28-foot tree

Answer 1

12/40 =0.3

28 *0.3 = 8.4

it will cast a 8.4 foot long shadow

Answer 2

Answer:

The shadow cast by a 28-foot tree is 8.4 foot.

Step-by-step explanation:

The rule of three is a way of solving problems of proportionality between three known values and one unknown, establishing a relationship of proportionality between all of them. In the case of direct proportionality, when one magnitude increases, the other increases (  or if one magnitude decreases, the other will also decrease)

This is an example of application of this rule:

40 foot tree ⇒ 12 foot shadow

28 foot tree ⇒ x foot shadow

Then, to solve and calculate the value of x, which is the value of the shadow cast by the 28-foot tree, perform the count:

x=$\frac{28*12}{40}$

x=$\frac{336}{40}$

x=8.4

This means that the shadow cast by a 28-foot tree is 8.4 foot.