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Finding the Fourth Proportional to 511.41, 705.65 and 312.20

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Solution

The fourth proportional to 511.41, 705.65 and 312.20 is: 430.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.41 : 705.65 = 312.20 : x
  2. Step 2: Convert to fraction form
    511.41/705.65 = 312.20/x
  3. Step 3: Cross multiply
    511.41x = 705.65 × 312.20
  4. Step 4: Simplify right side
    511.41x = 220,303.93
  5. Step 5: Solve for x
    x = 220,303.93/511.41
  6. Step 6: Final answer
    x = 430.78

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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.