Okay ppls I need major help on this pls and thanks

The second question is $2,484
3.5 percent of 2,400 is 84
84 + 2,400 = 2,484
Answer:
1) 6 weeks
2) 2484 dollars
3) 45 dollars
4) 815.10 dollars
5) 128.4 dollars
Step-by-step explanation:
1) By the 6th week, she will have saved $100 and the racket will cost $90.
2) 3.5% of 2400 is 84. Add 84 to 2400 and you get 2484.
3) 40% of 75 is 30. 30 plus 75 is 105. 150-105=45
4) .045 * 780 = 35.1
780 + 35.1 = 815.1
5) 15 * 8 = 120
120 * .07 = 8.4
8.4 +120 = 128.4