Seemingly, she doubles the amount of miles for this practice. So if she ran 88 miles after 44 practices that’s 44 multiplied by 2, to get how many practices she needs for 1010 miles you do the opposite of multiplication; division, so you do 1010/2 which gives you 505, and to check this answer you can do 505 x 2 (since it’s doubled) giving you 1010.