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Finding the Fourth Proportional to 427.90, 643.20 and 403.60

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Solution

The fourth proportional to 427.90, 643.20 and 403.60 is: 606.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.90 : 643.20 = 403.60 : x
  2. Step 2: Convert to fraction form
    427.90/643.20 = 403.60/x
  3. Step 3: Cross multiply
    427.90x = 643.20 × 403.60
  4. Step 4: Simplify right side
    427.90x = 259,595.52
  5. Step 5: Solve for x
    x = 259,595.52/427.90
  6. Step 6: Final answer
    x = 606.67

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.