The rope 2

The rope in the school gym is 10 1/2 feet long. Coach Hill tied a knot every 3/4 foot to make climbing easier. How many knots are in the rope?

Final Answer:

n =  13

Step-by-step explanation:

$$\begin{gathered} a=10\frac{1}{2}=10+\frac{1}{2}=\frac{10\cdot 2+1}{2}=\frac{20+1}{2}=\frac{21}{2}=10\frac{1}{2}=10.5\text{ft} \\ k=3/4=\frac{3}{4}=0.75\text{ft} \\ x=a/k=\frac{21}{2}/\frac{3}{4}=\frac{21}{2}:\frac{3}{4}=\frac{21}{2}\cdot \frac{4}{3}=\frac{21\cdot 4}{2\cdot 3}=\frac{84}{6}=14 \\ n=x-1=14-1=13 \end{gathered}$$

Try another example