Home / 1,280.10-1,920.40-500.07

Finding the Fourth Proportional to 1,280.10, 1,920.40 and 500.07

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Solution

The fourth proportional to 1,280.10, 1,920.40 and 500.07 is: 750.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.10 : 1,920.40 = 500.07 : x
  2. Step 2: Convert to fraction form
    1,280.10/1,920.40 = 500.07/x
  3. Step 3: Cross multiply
    1,280.10x = 1,920.40 × 500.07
  4. Step 4: Simplify right side
    1,280.10x = 960,331.93
  5. Step 5: Solve for x
    x = 960,331.93/1,280.10
  6. Step 6: Final answer
    x = 750.20

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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.