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Finding the Fourth Proportional to 780.69, 1,170.68 and 347.84

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Solution

The fourth proportional to 780.69, 1,170.68 and 347.84 is: 521.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.69 : 1,170.68 = 347.84 : x
  2. Step 2: Convert to fraction form
    780.69/1,170.68 = 347.84/x
  3. Step 3: Cross multiply
    780.69x = 1,170.68 × 347.84
  4. Step 4: Simplify right side
    780.69x = 407,201.74
  5. Step 5: Solve for x
    x = 407,201.74/780.69
  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.