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Finding the Fourth Proportional to 780.64, 1,171.12 and 347.68

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Solution

The fourth proportional to 780.64, 1,171.12 and 347.68 is: 521.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.64 : 1,171.12 = 347.68 : x
  2. Step 2: Convert to fraction form
    780.64/1,171.12 = 347.68/x
  3. Step 3: Cross multiply
    780.64x = 1,171.12 × 347.68
  4. Step 4: Simplify right side
    780.64x = 407,175.00
  5. Step 5: Solve for x
    x = 407,175.00/780.64
  6. Step 6: Final answer
    x = 521.59

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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.