The number of nights that are needed to cover 4 chapters of the science book by Anthony is 8.
A ratio is an ordered couple of numbers a and b, written as a/b where b can not equal 0. A proportion is an equation in which two ratios are set equal to each other.
Anthony reads 1/2 chapter of his science book each night.
He has 4 chapters left to read.
[tex]\begin{aligned} \rm \dfrac{1}{2} \ chapeter &\rightarrow 1 \rm \ night\\\\1 \ \rm chapter &\rightarrow 2 \ \rm nights\\\\4 \ \rm chapters &\rightarrow 8 \ \rm nights \end{aligned}[/tex]
More about the ratio and the proportion link is given below.
https://brainly.com/question/14335762
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