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Finding the Fourth Proportional to 628.56, 860.76 and 626.40

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Solution

The fourth proportional to 628.56, 860.76 and 626.40 is: 857.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.56 : 860.76 = 626.40 : x
  2. Step 2: Convert to fraction form
    628.56/860.76 = 626.40/x
  3. Step 3: Cross multiply
    628.56x = 860.76 × 626.40
  4. Step 4: Simplify right side
    628.56x = 539,180.06
  5. Step 5: Solve for x
    x = 539,180.06/628.56
  6. Step 6: Final answer
    x = 857.80

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.