Home / 1,421.06-1,960.90-861.66

Finding the Fourth Proportional to 1,421.06, 1,960.90 and 861.66

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Solution

The fourth proportional to 1,421.06, 1,960.90 and 861.66 is: 1,188.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,421.06 : 1,960.90 = 861.66 : x
  2. Step 2: Convert to fraction form
    1,421.06/1,960.90 = 861.66/x
  3. Step 3: Cross multiply
    1,421.06x = 1,960.90 × 861.66
  4. Step 4: Simplify right side
    1,421.06x = 1,689,626.94
  5. Step 5: Solve for x
    x = 1,689,626.94/1,421.06
  6. Step 6: Final answer
    x = 1,188.99

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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.