We look at the division of 715343 by 87 
The aim is to understand the frequency of 87 in 715343.

On to step 1:
The number 87 fits into 7 0 times, leaving a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 7 after subtracting 0 from 7.
Include the next digit (1) from the dividend after 7, then repeat: 71 / 87

On to step 2:
When dividing 71 by 87, we get 0 with a remainder of 71.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 71 and we're left with 71.
Include the next digit (5) from the dividend after 71, then repeat: 715 / 87

Advancing to step 3:
715 divided by 87 is 8 with a remainder of 19.
Write down 8 as next digit of the result. 
Result so far: 8.0
Subtracting 696 from 715 leaves us with 19.
Include the next digit (3) from the dividend after 19, then repeat: 193 / 87

On to step 4:
The number 87 fits into 193 2 times, leaving a remainder of 19.
Put 2 as the next digit of the answer. 
Result so far: 82.0
If we take 174 away from 193, we end up with 19.
Take the next digit (4) from the dividend and append it to 19, then repeat: 194 / 87

Advancing to step 5:
194 divided by 87 is 2 with a remainder of 20.
The next digit of our result is 2. 
Result so far: 822.0
The remainder is 20 after subtracting 174 from 194.
Bring next digit (3) of the dividend behind the 20 and repeat the process: 203 / 87

Going ahead to step 6:
When dividing 203 by 87, we get 2 with a remainder of 29.
Put 2 as the next digit of the answer. 
Result so far: 8222.0
Deduct 174 from 203 and we're left with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Going ahead to step 7:
The number 87 fits into 290 3 times, leaving a remainder of 29.
Record the quotient 3 as the next digit in the result. 
Result so far: 8222.3
Deduct 261 from 290 and we're left with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Moving on to step 8:
When dividing 290 by 87, we get 3 with a remainder of 29.
Put 3 as the next digit of the answer. 
Result so far: 8222.33
Subtract 261 from 290 to get 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

After the division, we end up with 8222.33 and a remainder of 0.029.