Nathan

Nathan is playing a trivia game. Each correct answer is worth 2 ½ points, and each incorrect answer is worth -¼ points. If he gets 35 questions correct and 32 questions incorrect, how many points does he have?

A. 87.5
B. 79.5
C. 75
D. 8

Correct answer:

x =  79 ¹⁄₂ = 159/2

Step-by-step explanation:

$$\begin{gathered} a=2\frac{1}{2}=2+\frac{1}{2}=\frac{2\cdot 2+1}{2}=\frac{4+1}{2}=\frac{5}{2}=2\frac{1}{2}=2.5 \\ b=-1/4=-\frac{1}{4}=-0.25 \\ x=35\cdot a+32\cdot b=35\cdot \frac{5}{2}+32\cdot \frac{-1}{4}=\frac{159}{2}=79\frac{1}{2}=79.5 \end{gathered}$$

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