Question

The levels of mercury in two different bodies of water are rising. In one body of water the initial measure of mercury is 0.05 parts per billion (ppb) and is rising at a rate of 0.1 ppb each year. In the second body of water the initial measure is 0.12 ppb and the rate of increase is 0.06 ppb each year.

After how many years will the amount of mercury be the same?

a. 0.5 years
b. 1.25 years
c. 1.75 years
d. 2.5 years

Answer 1

@dumbo

Answer 2

c is my best bet

Answer 3

@iGreen

Answer 4

this is really confusing im sorry

Answer 5

Your fine.

Answer 6

@gorv

Answer 7

let after x year it will be same

Answer 8

0.05+0.1*x=0.12+0.06*x
subtract 0.05 from both side

Answer 9

0.1x=0.12-0.05+0.06x
0.1x=0.07+0.06x
subtract 0.06x from both side
0.1x-0.06x=0.07
0.04x=0.07
divide both side by o.o4
x=0.07/0.04
x=7/4 year

Answer 10

x= 1 yeah 9 month

Answer 11

9 months isn't an option..

Answer 12

loll 7/4 year

Answer 13

what are the option

Answer 14

1.75 year

Answer 15

1 3/4

Answer 16

\[\frac{ 7 }{ 4 }=1.75=1 year 9 month ,,,,,, all are same\]