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Finding the Fourth Proportional to 909.78, 1,255.72 and 555.70

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Solution

The fourth proportional to 909.78, 1,255.72 and 555.70 is: 767.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    909.78 : 1,255.72 = 555.70 : x
  2. Step 2: Convert to fraction form
    909.78/1,255.72 = 555.70/x
  3. Step 3: Cross multiply
    909.78x = 1,255.72 × 555.70
  4. Step 4: Simplify right side
    909.78x = 697,803.60
  5. Step 5: Solve for x
    x = 697,803.60/909.78
  6. Step 6: Final answer
    x = 767.00

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.