Write an equation system based on the problem An equation for Lily's expense is ∴ 3.6f + s = 11.2 <u>(first equation)</u> An equation for Alan's expense is ∴ 5f + 2.5s = 20 <u>(second equation)</u> f stands for the price of a kilogram of flour, s stands for the price of a kilogram of sugar
From the first equation, solve for s 3.6f + s = 11.2 s = 11.2 - 3.6f
Subtitute s with (11.2 - 3.6f) in the second equation 5f + 2.5s = 20 5f + 2.5(11.2 - 3.6f) = 20 5f + 28 - 9f = 20 -4f + 28 = 20 -4f = 20 - 28 -4f = -8 f = -8/-4 f = 2 A kilogram of flour is $2
Subtitute f with 2 to find the value of s s = 11.2 - 3.6f s = 11.2 - 3.6(2) s = 11.2 - 7.2 s = 4 A kilogram of sugar is $4
Or 1 kilogram<span> = 2 pounds 3 ounces. To change from </span>KILOGRAMS<span> TO POUNDS we can multiply by 2.2. So is we have a 2kg bag of </span>flour<span> and we want to know what this is in pounds we can work it out like this: 2kg = 2 x 2.2lbs = 4.4lbs. A. Try these. </span>1<span>) 3kg = lbs. 2) 6kg = lbs. 3) 7kg = lbs. 4) 12kg = lbs. </span>5<span>) 14kg = lbs. 6(
