let's evaluate this expression
[tex]\pmb{\displaystyle\frac{2}{5}g+3h-6 }[/tex]
[tex]\pmb{\displaystyle\frac{2}{5} *10+3(6)-6}[/tex]
[tex]\pmb{\displaystyle\frac{2}{5} *10+18-6}[/tex]
[tex]\pmb{\displaystyle\frac{2}{5} *10+12}[/tex]
Multiply:
[tex]\pmb{\displaystyle\frac{2}{5} *\frac{10}{1} =\frac{20}{5} =4}[/tex]
Final Step:-
[tex]\pmb{4+12}[/tex]
[tex]\pmb{16}[/tex]
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Hope everything is clear; if you need any explanation/clarification, kindly let me know, and I'll comment and/or edit my answer :)