Question

If two thirds of a number is decreased by 4, the result is 56. find the number

Answer 1

$56+4=60\\\\60\times3=180\\\\180:2=\fbox{90}\\\\CHECK:\\\frac{2}{3}\times90-4=2\times30-4=60-4=56$

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$128-38=90\\\\90\times9=810\\\\810:5=\fbox{162}\\\\CHECK:\\\\38+\frac{5}{9}\times162=38+5\times18=38+90=128$

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$14.6-2.3=12.3\\\\12.3\times5=61.5\\\\61.5:3=\fbox{20.5}\\\\CHECK:\\\\\frac{3}{5}\times20.5+2.3=3\times4.1+2.3=12.3+2.3=14.6$

Answer 2

Let the number be x
There are actually 3 different statements - 

1. two-thirds of a number decreased by 5 is 56
2*x/3 - 4 =56
2*x/3=60
x=90

2. 38 added to 5/9 of number gives 128
i.e 5*x/9 + 38 = 128
5*x/9 = 90
x = 162

3. sum of 2.3 and 3/5 of number gives 14.6
i.e 2.3 + 3*x/5 = 14.6
3*x/5 = 12.3
x = 4.1*5
x = 20.5