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Finding the Fourth Proportional to 518.55, 777.86 and 210.40

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Solution

The fourth proportional to 518.55, 777.86 and 210.40 is: 315.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.55 : 777.86 = 210.40 : x
  2. Step 2: Convert to fraction form
    518.55/777.86 = 210.40/x
  3. Step 3: Cross multiply
    518.55x = 777.86 × 210.40
  4. Step 4: Simplify right side
    518.55x = 163,661.74
  5. Step 5: Solve for x
    x = 163,661.74/518.55
  6. Step 6: Final answer
    x = 315.61

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.