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Finding the Fourth Proportional to 343.09, 514.63 and 99.78

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Solution

The fourth proportional to 343.09, 514.63 and 99.78 is: 149.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    343.09 : 514.63 = 99.78 : x
  2. Step 2: Convert to fraction form
    343.09/514.63 = 99.78/x
  3. Step 3: Cross multiply
    343.09x = 514.63 × 99.78
  4. Step 4: Simplify right side
    343.09x = 51,350.59
  5. Step 5: Solve for x
    x = 51,350.59/343.09
  6. Step 6: Final answer
    x = 149.67

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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.