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Finding the Fourth Proportional to 642.83, 887.41 and 619.75

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Solution

The fourth proportional to 642.83, 887.41 and 619.75 is: 855.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.83 : 887.41 = 619.75 : x
  2. Step 2: Convert to fraction form
    642.83/887.41 = 619.75/x
  3. Step 3: Cross multiply
    642.83x = 887.41 × 619.75
  4. Step 4: Simplify right side
    642.83x = 549,971.74
  5. Step 5: Solve for x
    x = 549,971.74/642.83
  6. Step 6: Final answer
    x = 855.54

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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.