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Finding the Fourth Proportional to 891.83, 1,228.17 and 642.76

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Solution

The fourth proportional to 891.83, 1,228.17 and 642.76 is: 885.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    891.83 : 1,228.17 = 642.76 : x
  2. Step 2: Convert to fraction form
    891.83/1,228.17 = 642.76/x
  3. Step 3: Cross multiply
    891.83x = 1,228.17 × 642.76
  4. Step 4: Simplify right side
    891.83x = 789,418.55
  5. Step 5: Solve for x
    x = 789,418.55/891.83
  6. Step 6: Final answer
    x = 885.17

Related Problems

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Half scale
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Double scale
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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.