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Finding the Fourth Proportional to 405.88, 608.70 and 340.90

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Solution

The fourth proportional to 405.88, 608.70 and 340.90 is: 511.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.88 : 608.70 = 340.90 : x
  2. Step 2: Convert to fraction form
    405.88/608.70 = 340.90/x
  3. Step 3: Cross multiply
    405.88x = 608.70 × 340.90
  4. Step 4: Simplify right side
    405.88x = 207,505.83
  5. Step 5: Solve for x
    x = 207,505.83/405.88
  6. Step 6: Final answer
    x = 511.25

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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.