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Finding the Fourth Proportional to 803.21, 1,108.10 and 636.75

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Solution

The fourth proportional to 803.21, 1,108.10 and 636.75 is: 878.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    803.21 : 1,108.10 = 636.75 : x
  2. Step 2: Convert to fraction form
    803.21/1,108.10 = 636.75/x
  3. Step 3: Cross multiply
    803.21x = 1,108.10 × 636.75
  4. Step 4: Simplify right side
    803.21x = 705,579.49
  5. Step 5: Solve for x
    x = 705,579.49/803.21
  6. Step 6: Final answer
    x = 878.46

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.