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Finding the Fourth Proportional to 638.16, 881.08 and 490.52

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Solution

The fourth proportional to 638.16, 881.08 and 490.52 is: 677.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.16 : 881.08 = 490.52 : x
  2. Step 2: Convert to fraction form
    638.16/881.08 = 490.52/x
  3. Step 3: Cross multiply
    638.16x = 881.08 × 490.52
  4. Step 4: Simplify right side
    638.16x = 432,187.36
  5. Step 5: Solve for x
    x = 432,187.36/638.16
  6. Step 6: Final answer
    x = 677.24

Related Problems

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Half scale
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Double scale
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Similar ratio
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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.