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Finding the Fourth Proportional to 528.23, 728.78 and 318.32

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Solution

The fourth proportional to 528.23, 728.78 and 318.32 is: 439.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.23 : 728.78 = 318.32 : x
  2. Step 2: Convert to fraction form
    528.23/728.78 = 318.32/x
  3. Step 3: Cross multiply
    528.23x = 728.78 × 318.32
  4. Step 4: Simplify right side
    528.23x = 231,985.48
  5. Step 5: Solve for x
    x = 231,985.48/528.23
  6. Step 6: Final answer
    x = 439.18

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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.