a school, a library, and a store are on the same straight read. The school is located 12 miles from the store. The library is located between the school and the store and is 7.4 miles from the store. What is the distance in miles between the school and the library?

4.6 miles

Step-by-step explanation:

Subtract the distance of the library to the store from the store to the school.

12-7.4=4.6

there is only one way to arrange all the eight relative to each other because they are not distinct. we have

now there are nine places to place an (and not more than one in one place).   because we have four symbols, we need to choose four of these nine places to insert an . order does not matter because the are not distinct.

thus there are 1 · c(9,4) ways, or, if we calculate it,

thus there are 126 ways to form such "words."