Hello there!
24. He had 10 cards at the start.
25. y = 24
26. c = 38
Let's solve each problem:
24. So Charlie took away 4 and had 6 left, how many did he start with?
Add the 4 taken away back to what is left - 6 + 4 = 10 So, he had 10 cards at the start.
25. -5y multiplied by what equals 120? To solve, divide 120 by -5. 120/-5 = -24, so y = 24.
26. What minus 11 equals 27? add 11 to 27 to solve. 27 + 11 = 38 so c = 38.
I hope this was helpful! Have a great (rest of your) day!