Steve baked 55 batches of cookies in
one and one half hours. vondra baked 31
batches of cookies in 1 hour. which baker
made cookies at a greater rate of batches
per hour?

*answer this question by comparing unit rates

Basically, you need to divide these by the number of minutes it took to make them. So, for example:

Since one hour and a half equals 90 minutes, Steve baked cookies at a rate of 0.61111 (the one keeps repeating) per minute (55 divided by 90).

Since one hour equals 60 minutes, Vondra baked cookies at a rate of 0.516666 ( the six keeps repeating) per minute (31 divided by 60).

This means that Steve baked batches of cookies at a greater rate than Vondra.

(n^3 - n)

= n(n-1)(n+1)

since it is divisible by 3 and 2 ,because it is a multiple 3 consecutive number

if, n-1 is odd then n+1 is also odd, then it is a multiple of 9

but if, n-1 is even then n+1 is also even, then it is a multiple of 4

so, largest multiple = max(9*2, 4*3) = max(18, 12) = 18