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Finding the Fourth Proportional to 528.04, 728.90 and 321

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Solution

The fourth proportional to 528.04, 728.90 and 321 is: 443.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.04 : 728.90 = 321 : x
  2. Step 2: Convert to fraction form
    528.04/728.90 = 321/x
  3. Step 3: Cross multiply
    528.04x = 728.90 × 321
  4. Step 4: Simplify right side
    528.04x = 233,976.90
  5. Step 5: Solve for x
    x = 233,976.90/528.04
  6. Step 6: Final answer
    x = 443.10

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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.