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Finding the Fourth Proportional to 856.12, 1,280.82 and 612.76

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Solution

The fourth proportional to 856.12, 1,280.82 and 612.76 is: 916.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.12 : 1,280.82 = 612.76 : x
  2. Step 2: Convert to fraction form
    856.12/1,280.82 = 612.76/x
  3. Step 3: Cross multiply
    856.12x = 1,280.82 × 612.76
  4. Step 4: Simplify right side
    856.12x = 784,835.26
  5. Step 5: Solve for x
    x = 784,835.26/856.12
  6. Step 6: Final answer
    x = 916.74

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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.