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Finding the Fourth Proportional to 421.24, 581.28 and 303.40

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Solution

The fourth proportional to 421.24, 581.28 and 303.40 is: 418.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.24 : 581.28 = 303.40 : x
  2. Step 2: Convert to fraction form
    421.24/581.28 = 303.40/x
  3. Step 3: Cross multiply
    421.24x = 581.28 × 303.40
  4. Step 4: Simplify right side
    421.24x = 176,360.35
  5. Step 5: Solve for x
    x = 176,360.35/421.24
  6. Step 6: Final answer
    x = 418.67

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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.