Home / 780.12-1,170.41-318.15

Finding the Fourth Proportional to 780.12, 1,170.41 and 318.15

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Solution

The fourth proportional to 780.12, 1,170.41 and 318.15 is: 477.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.12 : 1,170.41 = 318.15 : x
  2. Step 2: Convert to fraction form
    780.12/1,170.41 = 318.15/x
  3. Step 3: Cross multiply
    780.12x = 1,170.41 × 318.15
  4. Step 4: Simplify right side
    780.12x = 372,364.35
  5. Step 5: Solve for x
    x = 372,364.35/780.12
  6. Step 6: Final answer
    x = 477.32

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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.