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Finding the Fourth Proportional to 860.15, 1,289.29 and 312.18

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Solution

The fourth proportional to 860.15, 1,289.29 and 312.18 is: 467.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.15 : 1,289.29 = 312.18 : x
  2. Step 2: Convert to fraction form
    860.15/1,289.29 = 312.18/x
  3. Step 3: Cross multiply
    860.15x = 1,289.29 × 312.18
  4. Step 4: Simplify right side
    860.15x = 402,490.55
  5. Step 5: Solve for x
    x = 402,490.55/860.15
  6. Step 6: Final answer
    x = 467.93

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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.