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Finding the Fourth Proportional to 658.68, 988.30 and 312.20

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Solution

The fourth proportional to 658.68, 988.30 and 312.20 is: 468.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.68 : 988.30 = 312.20 : x
  2. Step 2: Convert to fraction form
    658.68/988.30 = 312.20/x
  3. Step 3: Cross multiply
    658.68x = 988.30 × 312.20
  4. Step 4: Simplify right side
    658.68x = 308,547.26
  5. Step 5: Solve for x
    x = 308,547.26/658.68
  6. Step 6: Final answer
    x = 468.43

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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.