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Finding the Fourth Proportional to 685.62, 947.02 and 499.70

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Solution

The fourth proportional to 685.62, 947.02 and 499.70 is: 690.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.62 : 947.02 = 499.70 : x
  2. Step 2: Convert to fraction form
    685.62/947.02 = 499.70/x
  3. Step 3: Cross multiply
    685.62x = 947.02 × 499.70
  4. Step 4: Simplify right side
    685.62x = 473,225.89
  5. Step 5: Solve for x
    x = 473,225.89/685.62
  6. Step 6: Final answer
    x = 690.22

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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.