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Finding the Fourth Proportional to 688.93, 950.66 and 390.20

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Solution

The fourth proportional to 688.93, 950.66 and 390.20 is: 538.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.93 : 950.66 = 390.20 : x
  2. Step 2: Convert to fraction form
    688.93/950.66 = 390.20/x
  3. Step 3: Cross multiply
    688.93x = 950.66 × 390.20
  4. Step 4: Simplify right side
    688.93x = 370,942.29
  5. Step 5: Solve for x
    x = 370,942.29/688.93
  6. Step 6: Final answer
    x = 538.43

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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.