74.71 would be the answer to two decimal - if it is 523 ÷ 7, which as words is 523 divided by 7, but 523 divided into 7 could mean 7 ÷ 523. Unless you're saying that you are dividing the number 523 into 7 equal parts.
Note that the question asks to estimate the quotient, not to actually do the division problem. By having the multiplication table memorized, I know that 7 x 8 = 56, so I can use 7 x 80 = 560, and 7 x 7 = 49 so 7 x 70 = 490. The answer lies between 80 and 70. If you want to refine it a little, notice that 523 is about halfway between 490 and 560, so you could estimate that the answer is about 75.
7/420 = 1/60
5,200
74.7143
29.5714
47.4286
You do not need to estimate it - you can calculate its exact value! 6/7 divided by 2 = 3/7
42.1 divided by 5.97 is about 42 divided by 6, so the answer is around 7.
10,10,10,3
5.8271
6.877
1.1667
My estimate is roughly around 63.0000013