how would you show his problem as a bar model
A box of chalk and 2 staplers cost $10.3 boxes of chalk and 2 staplers cost $18.Find the total cost of 1 box of chalk
c + 2s = 10
3c + 2s = 18
subtract them:
2c = 8
c = 4
then
4+2s=10
s = 3
poor way to type it, at first I though the chalk and 2 staples cost $10.30
my real name is Lillianna
my grandma just wrote it like that
To show his problem as a bar model, you can use rectangles to represent the different items involved and their respective costs.
First, draw a rectangular bar to represent the total cost of $10 for a box of chalk and 2 staplers. Divide this rectangular bar into two parts: one representing the cost of the box of chalk and the other representing the cost of the two staplers. The size of each part will be proportional to their respective costs.
Next, draw a rectangular bar to represent the total cost of $18 for 3 boxes of chalk and 2 staplers. Again, divide this bar into two parts: one representing the cost of the 3 boxes of chalk and the other representing the cost of the two staplers.
Now, compare the two models and observe the change in the cost of the boxes of chalk. You will notice that the size of the part representing the cost of the box of chalk has increased by a factor of 3.
To find the total cost of 1 box of chalk, you can divide the increase in cost by 3. Subtract the initial cost of the box of chalk from the increased cost, and then divide it by 3. This will give you the cost of 1 box of chalk.
Alternatively, you can use an algebraic approach to solve the problem. Let's assume the cost of the box of chalk is "x".
From the given information, we can set up the following equation:
x + 2 = 10 (for the initial cost of a box of chalk and 2 staplers)
3x + 2 = 18 (for the increased cost of 3 boxes of chalk and 2 staplers)
Solving these equations will yield the value of "x", which represents the cost of 1 box of chalk.