Ratios/proportions problem?

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2 Answers
Nov 4, 2017

$10.5, $15.75, $0.7 respectively

Explanation:

Given that lb is the unit of pounds.

3 lb = 31 lb
4.5 lb = (9/2)
1 lb
0.2 lb = (1/5)*1 lb

Therefore answers are as follows:
(a) required amount
= 3*($3.50)
= $10.5

(b) required amount
= 9/2*($3.50)
= $15.75

(c) required amount
= 1/5*($3.50)
= $0.7

Another solving method: let $x be the value of n lb candies.
x/n = 3.50/1

(1)x = 3.50n

x=3.50n,
which gives the above calculations.

Nov 4, 2017

3lbs will cost = $10.50#

4.5lbs will cost = $15.75

0.2 lb will cost = $0.70#

Explanation:

If 1 lb costs $3.50, 2 lbs will cost twice the amount of $3.50 or 2*3.50=$7

Hence 3lbs will cost 3*3.50 = $10.50

4.5lbs will cost =4.5 * 3.50 = $15.75

0.2 lb will cost 0.2 * 3.50 = $0.70#