Answer:
[tex]39\frac{1}{2} \ in[/tex]
Step-by-step explanation:
we know that
The total wood needed is equal to
[tex]2[12\frac{1}{2} ]+2[7\frac{1}{4}][/tex]
Convert mixed number to an improper fraction
[tex]12\frac{1}{2}\ in=12+\frac{1}{2}=\frac{12*2+1}{2}=\frac{25}{2}=\frac{50}{4} \ in[/tex]
[tex]7\frac{1}{4}\ in=7+\frac{1}{4}=\frac{7*4+1}{4}=\frac{29}{4}\ in[/tex]
substitute
[tex]2[\frac{50}{4} ]+2[\frac{29}{4}][/tex]
[tex]\frac{100}{4}+\frac{58}{4}[/tex]
[tex]\frac{158}{4}=39.5=39\frac{1}{2} \ in[/tex]