Home / 1,349.40-1,861.88-789.76

Finding the Fourth Proportional to 1,349.40, 1,861.88 and 789.76

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Solution

The fourth proportional to 1,349.40, 1,861.88 and 789.76 is: 1,089.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,349.40 : 1,861.88 = 789.76 : x
  2. Step 2: Convert to fraction form
    1,349.40/1,861.88 = 789.76/x
  3. Step 3: Cross multiply
    1,349.40x = 1,861.88 × 789.76
  4. Step 4: Simplify right side
    1,349.40x = 1,470,438.35
  5. Step 5: Solve for x
    x = 1,470,438.35/1,349.40
  6. Step 6: Final answer
    x = 1,089.70

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1.5x scale

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.