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Finding the Fourth Proportional to 926.80, 1,389.80 and 378.80

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Solution

The fourth proportional to 926.80, 1,389.80 and 378.80 is: 568.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    926.80 : 1,389.80 = 378.80 : x
  2. Step 2: Convert to fraction form
    926.80/1,389.80 = 378.80/x
  3. Step 3: Cross multiply
    926.80x = 1,389.80 × 378.80
  4. Step 4: Simplify right side
    926.80x = 526,456.24
  5. Step 5: Solve for x
    x = 526,456.24/926.80
  6. Step 6: Final answer
    x = 568.04

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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.