431.2+826.4d=2910.4
431.2 is only the first day therefore it doesn't need the variable because the variable represents the number of days. 826.4 even says "each remaining day" referring to what the variable represents.
Let's just change your problem to 147 of 30%
"Of" is always equaling to multiplication (×)
Now, it would be easier to simplify
30% (147)
30% ÷ 100 = 0.3
0.3(147)
Now, we get to your answer which might be 44.1
I think that will be 1000
She ran 102 miles, if you want to know the total.
34
3
102
