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Finding the Fourth Proportional to 369.78, 555.21 and 309.30

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Solution

The fourth proportional to 369.78, 555.21 and 309.30 is: 464.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    369.78 : 555.21 = 309.30 : x
  2. Step 2: Convert to fraction form
    369.78/555.21 = 309.30/x
  3. Step 3: Cross multiply
    369.78x = 555.21 × 309.30
  4. Step 4: Simplify right side
    369.78x = 171,726.45
  5. Step 5: Solve for x
    x = 171,726.45/369.78
  6. Step 6: Final answer
    x = 464.40

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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.