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Finding the Fourth Proportional to 651.60, 978.57 and 618.75

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Solution

The fourth proportional to 651.60, 978.57 and 618.75 is: 929.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.60 : 978.57 = 618.75 : x
  2. Step 2: Convert to fraction form
    651.60/978.57 = 618.75/x
  3. Step 3: Cross multiply
    651.60x = 978.57 × 618.75
  4. Step 4: Simplify right side
    651.60x = 605,490.19
  5. Step 5: Solve for x
    x = 605,490.19/651.60
  6. Step 6: Final answer
    x = 929.24

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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.