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Finding the Fourth Proportional to 840.24, 1,260.06 and 429.12

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Solution

The fourth proportional to 840.24, 1,260.06 and 429.12 is: 643.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.24 : 1,260.06 = 429.12 : x
  2. Step 2: Convert to fraction form
    840.24/1,260.06 = 429.12/x
  3. Step 3: Cross multiply
    840.24x = 1,260.06 × 429.12
  4. Step 4: Simplify right side
    840.24x = 540,716.95
  5. Step 5: Solve for x
    x = 540,716.95/840.24
  6. Step 6: Final answer
    x = 643.53

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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.