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Finding the Fourth Proportional to 521.40, 719.16 and 455.79

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Solution

The fourth proportional to 521.40, 719.16 and 455.79 is: 628.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.40 : 719.16 = 455.79 : x
  2. Step 2: Convert to fraction form
    521.40/719.16 = 455.79/x
  3. Step 3: Cross multiply
    521.40x = 719.16 × 455.79
  4. Step 4: Simplify right side
    521.40x = 327,785.94
  5. Step 5: Solve for x
    x = 327,785.94/521.40
  6. Step 6: Final answer
    x = 628.67

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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.