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Finding the Fourth Proportional to 771.40, 1,157.19 and 284.79

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Solution

The fourth proportional to 771.40, 1,157.19 and 284.79 is: 427.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    771.40 : 1,157.19 = 284.79 : x
  2. Step 2: Convert to fraction form
    771.40/1,157.19 = 284.79/x
  3. Step 3: Cross multiply
    771.40x = 1,157.19 × 284.79
  4. Step 4: Simplify right side
    771.40x = 329,556.14
  5. Step 5: Solve for x
    x = 329,556.14/771.40
  6. Step 6: Final answer
    x = 427.22

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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.