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Finding the Fourth Proportional to 498.76, 688.28 and 312.36

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Solution

The fourth proportional to 498.76, 688.28 and 312.36 is: 431.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.76 : 688.28 = 312.36 : x
  2. Step 2: Convert to fraction form
    498.76/688.28 = 312.36/x
  3. Step 3: Cross multiply
    498.76x = 688.28 × 312.36
  4. Step 4: Simplify right side
    498.76x = 214,989.63
  5. Step 5: Solve for x
    x = 214,989.63/498.76
  6. Step 6: Final answer
    x = 431.05

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.