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Finding the Fourth Proportional to 405.80, 608.18 and 259.49

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Solution

The fourth proportional to 405.80, 608.18 and 259.49 is: 388.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.80 : 608.18 = 259.49 : x
  2. Step 2: Convert to fraction form
    405.80/608.18 = 259.49/x
  3. Step 3: Cross multiply
    405.80x = 608.18 × 259.49
  4. Step 4: Simplify right side
    405.80x = 157,818.80
  5. Step 5: Solve for x
    x = 157,818.80/405.80
  6. Step 6: Final answer
    x = 388.91

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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.