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Finding the Fourth Proportional to 659.32, 988.64 and 385.50

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Solution

The fourth proportional to 659.32, 988.64 and 385.50 is: 578.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.32 : 988.64 = 385.50 : x
  2. Step 2: Convert to fraction form
    659.32/988.64 = 385.50/x
  3. Step 3: Cross multiply
    659.32x = 988.64 × 385.50
  4. Step 4: Simplify right side
    659.32x = 381,120.72
  5. Step 5: Solve for x
    x = 381,120.72/659.32
  6. Step 6: Final answer
    x = 578.05

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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.