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Finding the Fourth Proportional to 840.06, 1,260.87 and 429.49

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Solution

The fourth proportional to 840.06, 1,260.87 and 429.49 is: 644.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.06 : 1,260.87 = 429.49 : x
  2. Step 2: Convert to fraction form
    840.06/1,260.87 = 429.49/x
  3. Step 3: Cross multiply
    840.06x = 1,260.87 × 429.49
  4. Step 4: Simplify right side
    840.06x = 541,531.06
  5. Step 5: Solve for x
    x = 541,531.06/840.06
  6. Step 6: Final answer
    x = 644.63

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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.