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Finding the Fourth Proportional to 776.72, 1,070.79 and 619.88

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Solution

The fourth proportional to 776.72, 1,070.79 and 619.88 is: 854.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    776.72 : 1,070.79 = 619.88 : x
  2. Step 2: Convert to fraction form
    776.72/1,070.79 = 619.88/x
  3. Step 3: Cross multiply
    776.72x = 1,070.79 × 619.88
  4. Step 4: Simplify right side
    776.72x = 663,755.95
  5. Step 5: Solve for x
    x = 663,755.95/776.72
  6. Step 6: Final answer
    x = 854.57

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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.