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Finding the Fourth Proportional to 420.19, 581.07 and 400.85

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Solution

The fourth proportional to 420.19, 581.07 and 400.85 is: 554.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.19 : 581.07 = 400.85 : x
  2. Step 2: Convert to fraction form
    420.19/581.07 = 400.85/x
  3. Step 3: Cross multiply
    420.19x = 581.07 × 400.85
  4. Step 4: Simplify right side
    420.19x = 232,922.69
  5. Step 5: Solve for x
    x = 232,922.69/420.19
  6. Step 6: Final answer
    x = 554.33

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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.