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Finding the Fourth Proportional to 521.40, 719.41 and 311.64

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Solution

The fourth proportional to 521.40, 719.41 and 311.64 is: 430.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.40 : 719.41 = 311.64 : x
  2. Step 2: Convert to fraction form
    521.40/719.41 = 311.64/x
  3. Step 3: Cross multiply
    521.40x = 719.41 × 311.64
  4. Step 4: Simplify right side
    521.40x = 224,200.99
  5. Step 5: Solve for x
    x = 224,200.99/521.40
  6. Step 6: Final answer
    x = 430.00

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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.