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Finding the Fourth Proportional to 505.90, 698.19 and 309.41

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Solution

The fourth proportional to 505.90, 698.19 and 309.41 is: 427.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.90 : 698.19 = 309.41 : x
  2. Step 2: Convert to fraction form
    505.90/698.19 = 309.41/x
  3. Step 3: Cross multiply
    505.90x = 698.19 × 309.41
  4. Step 4: Simplify right side
    505.90x = 216,026.97
  5. Step 5: Solve for x
    x = 216,026.97/505.90
  6. Step 6: Final answer
    x = 427.02

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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.