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Finding the Fourth Proportional to 390.68, 583.16 and 339.68

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Solution

The fourth proportional to 390.68, 583.16 and 339.68 is: 507.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.68 : 583.16 = 339.68 : x
  2. Step 2: Convert to fraction form
    390.68/583.16 = 339.68/x
  3. Step 3: Cross multiply
    390.68x = 583.16 × 339.68
  4. Step 4: Simplify right side
    390.68x = 198,087.79
  5. Step 5: Solve for x
    x = 198,087.79/390.68
  6. Step 6: Final answer
    x = 507.03

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.