Home / 780.24-1,170.87-415.29

Finding the Fourth Proportional to 780.24, 1,170.87 and 415.29

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Solution

The fourth proportional to 780.24, 1,170.87 and 415.29 is: 623.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.24 : 1,170.87 = 415.29 : x
  2. Step 2: Convert to fraction form
    780.24/1,170.87 = 415.29/x
  3. Step 3: Cross multiply
    780.24x = 1,170.87 × 415.29
  4. Step 4: Simplify right side
    780.24x = 486,250.60
  5. Step 5: Solve for x
    x = 486,250.60/780.24
  6. Step 6: Final answer
    x = 623.21

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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.