Home / 1,289.40-1,934.10-423.78

Finding the Fourth Proportional to 1,289.40, 1,934.10 and 423.78

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Solution

The fourth proportional to 1,289.40, 1,934.10 and 423.78 is: 635.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.40 : 1,934.10 = 423.78 : x
  2. Step 2: Convert to fraction form
    1,289.40/1,934.10 = 423.78/x
  3. Step 3: Cross multiply
    1,289.40x = 1,934.10 × 423.78
  4. Step 4: Simplify right side
    1,289.40x = 819,632.90
  5. Step 5: Solve for x
    x = 819,632.90/1,289.40
  6. Step 6: Final answer
    x = 635.67

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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.