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Finding the Fourth Proportional to 909.32, 1,255.03 and 645.08

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Solution

The fourth proportional to 909.32, 1,255.03 and 645.08 is: 890.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    909.32 : 1,255.03 = 645.08 : x
  2. Step 2: Convert to fraction form
    909.32/1,255.03 = 645.08/x
  3. Step 3: Cross multiply
    909.32x = 1,255.03 × 645.08
  4. Step 4: Simplify right side
    909.32x = 809,594.75
  5. Step 5: Solve for x
    x = 809,594.75/909.32
  6. Step 6: Final answer
    x = 890.33

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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.