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Finding the Fourth Proportional to 648.80, 890.82 and 631.89

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Solution

The fourth proportional to 648.80, 890.82 and 631.89 is: 867.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.80 : 890.82 = 631.89 : x
  2. Step 2: Convert to fraction form
    648.80/890.82 = 631.89/x
  3. Step 3: Cross multiply
    648.80x = 890.82 × 631.89
  4. Step 4: Simplify right side
    648.80x = 562,895.01
  5. Step 5: Solve for x
    x = 562,895.01/648.80
  6. Step 6: Final answer
    x = 867.60

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1.5x scale

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.