How much is five out of eighteen plus five out of twelve plus seven out of eighteen?

How much is five out of eighteen plus five out of twelve plus seven out of eighteen?

Five out of eighteen plus five out of twelve plus seven out of eighteen
=(5 out of 18 plus 7 out of 18) plus 5 out of 12
=12 out of 18 + 5 out of 12
=8 / 12 + 5 / 12
=13 out of 12

What's one eighth times nine quarters plus sixteen quarters divided by eight

1/8 * 9/25 +16/25 ÷8
=1/8 * （9/25+16/25）
=1/8

999 1 / 9 minus 998 8 / 9
According to (a + b) * (a-b) = the square of a - the square of B = (a + b) * (a-b)

2/9
It should be
999+1/9-998-8/9

Compare 9 out of 20 with 1 out of 2, compare 5 out of 7 with 2 out of 3, compare 7 out of 15 with 11 out of 15
Compare 13 out of 3 with 4 and 1 out of 3 with 5 out of 4 with 19 out of 4

9 out of 20 is less than 1 out of 2, 5 out of 7 is more than 2 out of 3, 7 out of 15 is less than 11 out of 15, 3 out of 10 is less than 2 out of 5, 13 out of 3 is equal to 4 and 1 out of 3, and 5 is more than 19 out of 4