Home / 1,243.55-1,865.34-421.76

Finding the Fourth Proportional to 1,243.55, 1,865.34 and 421.76

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Solution

The fourth proportional to 1,243.55, 1,865.34 and 421.76 is: 632.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,243.55 : 1,865.34 = 421.76 : x
  2. Step 2: Convert to fraction form
    1,243.55/1,865.34 = 421.76/x
  3. Step 3: Cross multiply
    1,243.55x = 1,865.34 × 421.76
  4. Step 4: Simplify right side
    1,243.55x = 786,730.46
  5. Step 5: Solve for x
    x = 786,730.46/1,243.55
  6. Step 6: Final answer
    x = 632.65

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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.