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Finding the Fourth Proportional to 521.25, 719.45 and 311.55

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Solution

The fourth proportional to 521.25, 719.45 and 311.55 is: 430.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.25 : 719.45 = 311.55 : x
  2. Step 2: Convert to fraction form
    521.25/719.45 = 311.55/x
  3. Step 3: Cross multiply
    521.25x = 719.45 × 311.55
  4. Step 4: Simplify right side
    521.25x = 224,147.63
  5. Step 5: Solve for x
    x = 224,147.63/521.25
  6. Step 6: Final answer
    x = 430.02

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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.