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Finding the Fourth Proportional to 888.75, 1,228.08 and 639.66

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Solution

The fourth proportional to 888.75, 1,228.08 and 639.66 is: 883.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    888.75 : 1,228.08 = 639.66 : x
  2. Step 2: Convert to fraction form
    888.75/1,228.08 = 639.66/x
  3. Step 3: Cross multiply
    888.75x = 1,228.08 × 639.66
  4. Step 4: Simplify right side
    888.75x = 785,553.65
  5. Step 5: Solve for x
    x = 785,553.65/888.75
  6. Step 6: Final answer
    x = 883.89

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1.5x scale

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.