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Finding the Fourth Proportional to 841.80, 1,261.95 and 402.78

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Solution

The fourth proportional to 841.80, 1,261.95 and 402.78 is: 603.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    841.80 : 1,261.95 = 402.78 : x
  2. Step 2: Convert to fraction form
    841.80/1,261.95 = 402.78/x
  3. Step 3: Cross multiply
    841.80x = 1,261.95 × 402.78
  4. Step 4: Simplify right side
    841.80x = 508,288.22
  5. Step 5: Solve for x
    x = 508,288.22/841.80
  6. Step 6: Final answer
    x = 603.81

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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.