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Finding the Fourth Proportional to 305.90, 419.93 and 281.30

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Solution

The fourth proportional to 305.90, 419.93 and 281.30 is: 386.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.90 : 419.93 = 281.30 : x
  2. Step 2: Convert to fraction form
    305.90/419.93 = 281.30/x
  3. Step 3: Cross multiply
    305.90x = 419.93 × 281.30
  4. Step 4: Simplify right side
    305.90x = 118,123.86
  5. Step 5: Solve for x
    x = 118,123.86/305.90
  6. Step 6: Final answer
    x = 386.15

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.