Describe the use of the 10X10 grid to solve the following problem.Your telephone bill was $80 after a %25 increase. What was your bill before the increase?
To solve this problem using a 10x10 grid, follow these steps:
1. Set up a 10x10 grid.
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2. Divide the grid into 4 equal parts to represent the $80 bill.
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3. Shade one part of the grid to represent the 25% increase.
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4. Count the shaded squares to determine the value of one part of the grid.
In this case, there are 9 shaded squares.
5. Divide the total value of the grid, which is $80, by the number of shaded squares (9) to find the value of one part of the grid.
$80 ÷ 9 = $8.88 (rounded to two decimal places)
6. Multiply the value of one part of the grid by 100 to find the total bill before the increase.
$8.88 × 100 = $888 (rounded to the nearest whole number)
Therefore, your bill before the 25% increase was $888.
To solve this problem using a 10x10 grid, we can start by finding what amount the 25% increase represents in relation to the final bill of $80.
Step 1: Represent the final bill of $80 on the 10x10 grid. Draw a rectangle on the grid to represent the total bill.
Step 2: Divide the rectangle into four equal parts, representing 100% of the bill. This is because the final bill represents 100% of the amount we want to find.
Step 3: Take one of the four equal parts and shade it. This shaded part represents the 25% increase added to the final bill.
Step 4: Now, look at the remaining three equal parts (75% of the bill), which represent the bill amount before the increase.
Step 5: Calculate the value of one of the three equal parts. Divide the final bill ($80) by 4 since there are four equal parts (each representing 25%).
Step 6: Multiply the value of one of the three equal parts by 3 to find the bill amount before the increase.
For this specific problem, the calculation would be: ($80 ÷ 4) × 3 = $60.
Therefore, the bill amount before the 25% increase was $60.