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Finding the Fourth Proportional to 685.68, 947.49 and 519.60

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Solution

The fourth proportional to 685.68, 947.49 and 519.60 is: 718.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.68 : 947.49 = 519.60 : x
  2. Step 2: Convert to fraction form
    685.68/947.49 = 519.60/x
  3. Step 3: Cross multiply
    685.68x = 947.49 × 519.60
  4. Step 4: Simplify right side
    685.68x = 492,315.80
  5. Step 5: Solve for x
    x = 492,315.80/685.68
  6. Step 6: Final answer
    x = 718.00

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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.