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Finding the Fourth Proportional to 688.72, 949.80 and 492.16

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Solution

The fourth proportional to 688.72, 949.80 and 492.16 is: 678.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.72 : 949.80 = 492.16 : x
  2. Step 2: Convert to fraction form
    688.72/949.80 = 492.16/x
  3. Step 3: Cross multiply
    688.72x = 949.80 × 492.16
  4. Step 4: Simplify right side
    688.72x = 467,453.57
  5. Step 5: Solve for x
    x = 467,453.57/688.72
  6. Step 6: Final answer
    x = 678.73

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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.