A construction company is preparing 10 acres of land for a new housing community. The land contains large rocks that
need to be removed. A machine removes 15 rocks from 360
square feet of land.
1 acre = 43,560 square feet
About how many rocks will need to be removed from the 10
acres of land?

A

Step-by-step explanation:

43560/360 = 121

131x15 = 1815 rocks per acre

1815 x 10 acres = 18150 rocks

you can not drow on this

step-by-step explanation:

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional