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Finding the Fourth Proportional to 643, 963.78 and 318.02

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Solution

The fourth proportional to 643, 963.78 and 318.02 is: 476.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    643 : 963.78 = 318.02 : x
  2. Step 2: Convert to fraction form
    643/963.78 = 318.02/x
  3. Step 3: Cross multiply
    643x = 963.78 × 318.02
  4. Step 4: Simplify right side
    643x = 306,501.32
  5. Step 5: Solve for x
    x = 306,501.32/643
  6. Step 6: Final answer
    x = 476.67

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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.