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Finding the Fourth Proportional to 880.42, 1,321.20 and 418.72

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Solution

The fourth proportional to 880.42, 1,321.20 and 418.72 is: 628.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    880.42 : 1,321.20 = 418.72 : x
  2. Step 2: Convert to fraction form
    880.42/1,321.20 = 418.72/x
  3. Step 3: Cross multiply
    880.42x = 1,321.20 × 418.72
  4. Step 4: Simplify right side
    880.42x = 553,211.45
  5. Step 5: Solve for x
    x = 553,211.45/880.42
  6. Step 6: Final answer
    x = 628.35

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.