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Finding the Fourth Proportional to 840.92, 1,260.28 and 430.16

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Solution

The fourth proportional to 840.92, 1,260.28 and 430.16 is: 644.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.92 : 1,260.28 = 430.16 : x
  2. Step 2: Convert to fraction form
    840.92/1,260.28 = 430.16/x
  3. Step 3: Cross multiply
    840.92x = 1,260.28 × 430.16
  4. Step 4: Simplify right side
    840.92x = 542,122.04
  5. Step 5: Solve for x
    x = 542,122.04/840.92
  6. Step 6: Final answer
    x = 644.68

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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.