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Finding the Fourth Proportional to 659.96, 990.78 and 558.60

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Solution

The fourth proportional to 659.96, 990.78 and 558.60 is: 838.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.96 : 990.78 = 558.60 : x
  2. Step 2: Convert to fraction form
    659.96/990.78 = 558.60/x
  3. Step 3: Cross multiply
    659.96x = 990.78 × 558.60
  4. Step 4: Simplify right side
    659.96x = 553,449.71
  5. Step 5: Solve for x
    x = 553,449.71/659.96
  6. Step 6: Final answer
    x = 838.61

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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.