How much flower is in the bag now ?

Question

Kay had 5026 grams of flower in a canister. She bought a 4157 gram bag of flower. She poured some flower from the bag to the canister. As a result the mass of the flower in the canister is now twice the mass of the flower left in the bag. How much flour is in the bag now ?

Answer 1

Let x = the amount of flour poured from the bag to the canister.  

 

main equation:  amount in the canister = 2(amount in the bag)

 

The canister would increase by x, the bag would decrease by x.

amount in the canister is 5026+x

amount is the bag is 4157-x

 

plugging this into the main equation

5026+x = 2(4157-x)  solve this equation for x, first use the distributive property on the right side.

5026+x=8314-2x  add 2x to both sides of the equation

5026+3x=8314  subtract 5026 from both sides of the equation

3x=3288 divide both sides by 3

x=1096  this is the amount of flour poured from the bag to the canister.  This is not what is asked for.  The amount left in the bag is

 

4157-x or 4157-1096 = 3061 grams of flour in the bag