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Finding the Fourth Proportional to 645.08, 890.22 and 369.08

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Solution

The fourth proportional to 645.08, 890.22 and 369.08 is: 509.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.08 : 890.22 = 369.08 : x
  2. Step 2: Convert to fraction form
    645.08/890.22 = 369.08/x
  3. Step 3: Cross multiply
    645.08x = 890.22 × 369.08
  4. Step 4: Simplify right side
    645.08x = 328,562.40
  5. Step 5: Solve for x
    x = 328,562.40/645.08
  6. Step 6: Final answer
    x = 509.34

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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.