Answer:
15 days
Explanation:
a) Li uses = 8.4 grams of sugar every day in her tea.
Li’s sugar canister contains = 128 grams of sugar
Let x be the number of days at which Li uses sugar in her tea
The Equation for Li's sugar usuage =
y = 128 - 8.4x ......... Equation 1
Where y , the quantity of sugar left.
b) Sue uses = 12.6 grams of sugar every day in her coffee.
Sue’s canister contains = 191 grams
Let x be the number of days at which Sue uses sugar in her tea
The Equation for Sue's sugar usuage =
y = 191 - 12.6x .........Equation 2
Where y , the quantity of sugar left.
We are asked in the question, how many days will Li and Sue have the same amount of sugar in their canisters
We would equate both equations to each other.
Equation 1 = Equation 2
y = 128 - 8.4x = y = 191 - 12.6x
128 - 8.4x = 191 - 12.6x
-8.4x + 12.6x = 191 - 128
4.2x = 63
x = 63/4.2
x = 15
15 days
Therefore Li and Sue have the same amount of sugar in their canisters after 15 days.
To confirm
Equation 1 = Equation 2
y = 128 - 8.4x = y = 196 - 12.6 × 15
y = 128 - 8.4 × 15 = y = 196 - 12.6 × 15
y = 128 - 126 = y = 196 - 189
y = 2 = y = 2