Question

1 1/2 +7 4/5. one whole number ,one over 2 plus 7 whole number 4/5

Answer 1

Given the following sum:

`1(1)/(2)+7(4)/(5)`

For each term we have (from mixed numbers to fractions):

`\begin{gathered} 1(1)/(2)=(1\cdot2+1)/(2)=(2+1)/(2)=(3)/(2) \\ \\ 7(4)/(5)=(7\cdot5+4)/(5)=(35+4)/(5)=(39)/(5) \end{gathered}`

Then:

`1(1)/(2)+7(4)/(5)=(3)/(2)+(39)/(5)`

Using the cross product method:

`\begin{gathered} (3)/(2)+(39)/(5)=(3\cdot5+39\cdot2)/(2\cdot5)=(15+78)/(10)=(93)/(10) \\ \\ \therefore1(1)/(2)+7(4)/(5)=(93)/(10) \end{gathered}`

In mixed form:

`1(1)/(2)+7(4)/(5)=9(3)/(10)`