Home / 780.14-1,169.27-286.15

Finding the Fourth Proportional to 780.14, 1,169.27 and 286.15

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Solution

The fourth proportional to 780.14, 1,169.27 and 286.15 is: 428.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.14 : 1,169.27 = 286.15 : x
  2. Step 2: Convert to fraction form
    780.14/1,169.27 = 286.15/x
  3. Step 3: Cross multiply
    780.14x = 1,169.27 × 286.15
  4. Step 4: Simplify right side
    780.14x = 334,586.06
  5. Step 5: Solve for x
    x = 334,586.06/780.14
  6. Step 6: Final answer
    x = 428.88

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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.