Home / 2,812.80-4,220.64-1,989.30

Finding the Fourth Proportional to 2,812.80, 4,220.64 and 1,989.30

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Solution

The fourth proportional to 2,812.80, 4,220.64 and 1,989.30 is: 2,984.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,812.80 : 4,220.64 = 1,989.30 : x
  2. Step 2: Convert to fraction form
    2,812.80/4,220.64 = 1,989.30/x
  3. Step 3: Cross multiply
    2,812.80x = 4,220.64 × 1,989.30
  4. Step 4: Simplify right side
    2,812.80x = 8,396,119.15
  5. Step 5: Solve for x
    x = 8,396,119.15/2,812.80
  6. Step 6: Final answer
    x = 2,984.97

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.