Which of these is the best deal? [note: there are two pints in a quart, and four quarts in a gallon] question 6 options: a) one quart of milk for $1 b) 1 gallon of milk for $2 c) two quarts of milk for $1.50 d) one pint of milk for 50 cents

B

Step-by-step explanation:

Note:

1 gal = 4 quarts

1 pint = 0.5 quart

Re-writing all the choices in dollars and quarts and calculating how much each quart costs

A)  $1 per 1 quart

B)  $2 per gallon = $2 per 4 quarts = $2 ÷ 4 quarts = $0.50 per quart

C)  $1.50 per 2 quarts = $1.50 ÷ 2 quarts = $0.75 per quart

D)  $0.50 per 1 pint = $0.50 per 0.5 quart = $0.50 ÷ 0.5 quart = $1 per quart

If you compare all of the above, it is clear that answer B ($0.50 per quart) is the cheapest rate and hence the best deal.

(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

a is the right answer