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Finding the Fourth Proportional to 780.40, 1,170.28 and 293.19

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Solution

The fourth proportional to 780.40, 1,170.28 and 293.19 is: 439.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.40 : 1,170.28 = 293.19 : x
  2. Step 2: Convert to fraction form
    780.40/1,170.28 = 293.19/x
  3. Step 3: Cross multiply
    780.40x = 1,170.28 × 293.19
  4. Step 4: Simplify right side
    780.40x = 343,114.39
  5. Step 5: Solve for x
    x = 343,114.39/780.40
  6. Step 6: Final answer
    x = 439.66

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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.