Question

Courier charges for packages to a certain destination are 65 cents for the first 250 grams and 10 cents for each additional 100 grams of part thereof. What could be the weight in grams of a package for which the charge is $1.55?

Answer 1

1050 g < weight ≤ 1150 g

Explanation:

Let w represent the weight of the package in grams. The the number of 100-gram increments after the first 250 grams is given by ...

⌈(w-250)/100⌉ . . . . . . . where ⌈ ⌉ signifies the ceiling function

and the charges for a package exceeding 250 grams will be ...

0.65 + 0.10⌈(w -250)/100⌉ = 1.55

0.10⌈(w -250)/100⌉ = 0.90 . . . . . . . . subtract 0.65

⌈(w -250)/100⌉ = 9 . . . . . . . . . . . . . . . divide by 0.10

8 < (w-250)/100 ≤ 9 . . . . . . . . . . . . . . meaning of ceiling function

800 < w -250 ≤ 900 . . . . . . . . . . . . . multiply by 100

1050 < w ≤ 1150 . . . . . . . . . . . . . . . . . add 250

The weight in grams could be greater than 1050 and at most 1150 for a charge of $1.55.