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Finding the Fourth Proportional to 511.39, 705.55 and 312.15

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Solution

The fourth proportional to 511.39, 705.55 and 312.15 is: 430.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.39 : 705.55 = 312.15 : x
  2. Step 2: Convert to fraction form
    511.39/705.55 = 312.15/x
  3. Step 3: Cross multiply
    511.39x = 705.55 × 312.15
  4. Step 4: Simplify right side
    511.39x = 220,235.29
  5. Step 5: Solve for x
    x = 220,235.29/511.39
  6. Step 6: Final answer
    x = 430.66

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1.5x scale

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.