Answer:
[tex]\sf 178.1[/tex]
Step-by-step explanation:
[tex]\sf 12.3s+11.5t[/tex]
[tex]\sf s=7[/tex]
[tex]\sf t=8[/tex]
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[tex]\sf 12.3\left(7\right)+11.5\left(8\right)[/tex]
[tex]\sf 12.3\times \:7+11.5\times \:8[/tex]
[tex]\sf 12.3\times \:7=86.1[/tex]
[tex]\sf 11.5\times \:8=92[/tex]
[tex]\sf 86.1+92[/tex]
[tex]\sf 178.1[/tex]
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HOPE IT HELPS!!
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