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Finding the Fourth Proportional to 515.09, 710.84 and 279.05

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Solution

The fourth proportional to 515.09, 710.84 and 279.05 is: 385.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.09 : 710.84 = 279.05 : x
  2. Step 2: Convert to fraction form
    515.09/710.84 = 279.05/x
  3. Step 3: Cross multiply
    515.09x = 710.84 × 279.05
  4. Step 4: Simplify right side
    515.09x = 198,355.48
  5. Step 5: Solve for x
    x = 198,355.48/515.09
  6. Step 6: Final answer
    x = 385.09

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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.