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Finding the Fourth Proportional to 515.49, 711.36 and 305.64

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Solution

The fourth proportional to 515.49, 711.36 and 305.64 is: 421.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.49 : 711.36 = 305.64 : x
  2. Step 2: Convert to fraction form
    515.49/711.36 = 305.64/x
  3. Step 3: Cross multiply
    515.49x = 711.36 × 305.64
  4. Step 4: Simplify right side
    515.49x = 217,420.07
  5. Step 5: Solve for x
    x = 217,420.07/515.49
  6. Step 6: Final answer
    x = 421.77

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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.