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Finding the Fourth Proportional to 399.51, 551.19 and 259.80

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Solution

The fourth proportional to 399.51, 551.19 and 259.80 is: 358.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.51 : 551.19 = 259.80 : x
  2. Step 2: Convert to fraction form
    399.51/551.19 = 259.80/x
  3. Step 3: Cross multiply
    399.51x = 551.19 × 259.80
  4. Step 4: Simplify right side
    399.51x = 143,199.16
  5. Step 5: Solve for x
    x = 143,199.16/399.51
  6. Step 6: Final answer
    x = 358.44

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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.