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Finding the Fourth Proportional to 518.16, 715.08 and 308.40

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Solution

The fourth proportional to 518.16, 715.08 and 308.40 is: 425.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.16 : 715.08 = 308.40 : x
  2. Step 2: Convert to fraction form
    518.16/715.08 = 308.40/x
  3. Step 3: Cross multiply
    518.16x = 715.08 × 308.40
  4. Step 4: Simplify right side
    518.16x = 220,530.67
  5. Step 5: Solve for x
    x = 220,530.67/518.16
  6. Step 6: Final answer
    x = 425.60

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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.