How many 1/9s are in 31

279

Step-by-step explanation:

Lets do the following:

How many 1/9 are there in 1? Easy! 9. We can corroborate this by summing 1/9 nine times of multiplying 1/9 nine times. In both cases the result is 9.

Then, how many 1 are there in 31? Easier! 31. Is we sum the number 1 thirty one times, the result is 31.

Now let join both results:

If each 1 has nine 1/9, and there are thirty one 1s in 31, then in 31 we have 31*9=279 1/9s. This is:

31*1 = 31 * 9 (1/9) = 279 * (1/9)