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Finding the Fourth Proportional to 645.74, 890.82 and 380.10

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Solution

The fourth proportional to 645.74, 890.82 and 380.10 is: 524.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.74 : 890.82 = 380.10 : x
  2. Step 2: Convert to fraction form
    645.74/890.82 = 380.10/x
  3. Step 3: Cross multiply
    645.74x = 890.82 × 380.10
  4. Step 4: Simplify right side
    645.74x = 338,600.68
  5. Step 5: Solve for x
    x = 338,600.68/645.74
  6. Step 6: Final answer
    x = 524.36

Related Problems

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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.