The ratio of the length of a rectangular field to its width is 10:7 if the width of the field is 70 meters find the perimeter of the field.

length = L

width = w

Ratio = L:w = 10:7 = L:70
10:7 = L:70
10/7 = L/70
cross multiply
700 = 7L
L = 100

L = 100, w = 70
P = 2w + 2L
P = ?

To find the perimeter of the rectangular field, we need to know the length of the field.

Given that the ratio of the length to the width is 10:7, we can set up a proportion to solve for the length.

Let's represent the length of the field as L. The given width is 70 meters, so the proportion can be set up as:

L / 70 = 10 / 7

To solve this proportion, we can cross-multiply:

7L = 70 * 10

7L = 700

Finally, divide both sides by 7 to isolate L:

L = 700 / 7

L = 100

Therefore, the length of the field is 100 meters.

Now, we can find the perimeter by using the formula P = 2(L + W), where P is the perimeter, L is the length, and W is the width.

Substituting the values we found:

P = 2(100 + 70)

P = 2(170)

P = 340

Therefore, the perimeter of the field is 340 meters.

let the length be 10x

let the width be 7x , ( notice the ratio 10x : 7x = 10:7 )

given : 7x = 70
x = 10

Perimeter = 2(10x+7x) = 34x = 340

check:
length =100
width =70
perilmeter = 100+100+70+70 = 340