It will be 21/40
probability getting both white marbles
3/8×4/10=12/80
probability getting both black marbles
5/8×6/10=30/80
12/80+30/80=42/80= 21/80
If you put them into to proportion
156/400 and then put a variable for the unknown x/1200
1200 divided by 400 = 3
156 times 3 = 468
468 order salad out of 1200
So u turn the percent into a decimal.
0.10
Now multiply 1200 * 0.10
1200*0.10= 120 ( 120 is the amount that is gonna increase)
So if it says 5 years, than your gonna multiply 120 * 5
120*5 =600
So your gonna add 600 to 1200.
So in five years your gonna be making 1,800.
An easier way would be to use prt
Principle * rate * time
1200 * 0.10* 5
= 600
So now you just add 600 to 1200
= 1800
