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6 out of 7 plus 2 out of 9 minus 1 out of 21
6 out of 7 plus 2 out of 9 minus 1 out of 21
=54 / 63 + 14 / 63-3 / 63
=65 out of 63
Write a natural number that is 21 out of 7 and 30 out of 6. How many do you think it is possible to write
21/7＝3
30/6＝5
So there is only one number like 4
5 / 7 of 21 is equal to 1 / 2 of a number. What is the number?
Lie equation
30
21*5/7=15
15*2=30
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