List all the multiples of the numbers:
2: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100
5: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100
6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72, 78, 84, 90, 96
9: 9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99
The least common multiple of 2, 5, 6, and 9 is 90.
If you already know that you have . . .
1$ after week 1
2$ after week 2
4$ after week 3
8$ after week 4
. . . You can then tell that every week the money you save doubles (times 2)
So to continue . . . .
16$ after week 5
32$ after week 6
64$ after week 7
128$ after week 8
256$ after week 9
512$ after week 10
You will then know that after ten weeks u will have 512$ which is answer choice D.
Hope this helps! :)
Let's solve for f.
y=f−1x
Step 1: Flip the equation.
f−x=y
Step 2: Add x to both sides.
f−x+x=y+x
f=x+y
Answer:
f=x+y
