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Finding the Fourth Proportional to 659.43, 988.74 and 312.87

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Solution

The fourth proportional to 659.43, 988.74 and 312.87 is: 469.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.43 : 988.74 = 312.87 : x
  2. Step 2: Convert to fraction form
    659.43/988.74 = 312.87/x
  3. Step 3: Cross multiply
    659.43x = 988.74 × 312.87
  4. Step 4: Simplify right side
    659.43x = 309,347.08
  5. Step 5: Solve for x
    x = 309,347.08/659.43
  6. Step 6: Final answer
    x = 469.11

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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.