If this is represented by a linear function, then we know that the amount of money decreases at an unchanging amount. Knowing this, and knowing that on day 8, she had 2400, we simply just add 2400 to 8 100's:
2400 + 8*100 = 2400 + 800
Carrie initially had $3200, or Option C.
Try this:
1. sum of numbers is x+y=67, the difference between them is x-y=11
2. it is possible to make up and resolve the system:
The correct answer would be, 300,060,520
2 tens, and 8 ones. I say this because 20 = 10 + 10 so, two tens. 8= 1+1+1+1+1+1+1+1 so, eight ones.