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Finding the Fourth Proportional to 498.70, 688.08 and 312.18

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Solution

The fourth proportional to 498.70, 688.08 and 312.18 is: 430.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.70 : 688.08 = 312.18 : x
  2. Step 2: Convert to fraction form
    498.70/688.08 = 312.18/x
  3. Step 3: Cross multiply
    498.70x = 688.08 × 312.18
  4. Step 4: Simplify right side
    498.70x = 214,804.81
  5. Step 5: Solve for x
    x = 214,804.81/498.70
  6. Step 6: Final answer
    x = 430.73

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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.