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Finding the Fourth Proportional to 521.55, 781.25 and 328.23

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Solution

The fourth proportional to 521.55, 781.25 and 328.23 is: 491.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.55 : 781.25 = 328.23 : x
  2. Step 2: Convert to fraction form
    521.55/781.25 = 328.23/x
  3. Step 3: Cross multiply
    521.55x = 781.25 × 328.23
  4. Step 4: Simplify right side
    521.55x = 256,428.05
  5. Step 5: Solve for x
    x = 256,428.05/521.55
  6. Step 6: Final answer
    x = 491.67

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.