8/5 is rational. It is expressed as a ratio of two integers.
√4 = 2 = 2/1 . This is rational because it expressed as ratio of two integers.
√64 = 8. This is rational because it expressed as ratio of two integers.
√10 = 3.16227..... The decimal part does not end and it is irrational because it can not be expressed as ratio of two integers.
Therefore √10 is irrational.
1.54 + 2.37
= (1 + 5/10 + 4/100) + (2 + 3/10 + 7/100)
= 1 + 5/10 + 4/100 + 2 + 3/10 + 7/100
= 3 + 8/10 + 11/100
= 3 + 8/10 + (10/100 + 1/100)
= 3 + 8/10 + (1/10 + 1/100)
= 3 + 8/10 + 1/10 + 1/100
= 3 + 9/10 + 1/100
= 3.91
Just add to find X
20 + 60 = 80
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X = 80
To make sure plug it in
80 - 60 = 20
The equation is true
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x = 80 is your answer