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Finding the Fourth Proportional to 648.90, 895.32 and 620.55

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Solution

The fourth proportional to 648.90, 895.32 and 620.55 is: 856.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.90 : 895.32 = 620.55 : x
  2. Step 2: Convert to fraction form
    648.90/895.32 = 620.55/x
  3. Step 3: Cross multiply
    648.90x = 895.32 × 620.55
  4. Step 4: Simplify right side
    648.90x = 555,590.83
  5. Step 5: Solve for x
    x = 555,590.83/648.90
  6. Step 6: Final answer
    x = 856.20

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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.