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Finding the Fourth Proportional to 499.56, 689.61 and 388.77

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Solution

The fourth proportional to 499.56, 689.61 and 388.77 is: 536.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.56 : 689.61 = 388.77 : x
  2. Step 2: Convert to fraction form
    499.56/689.61 = 388.77/x
  3. Step 3: Cross multiply
    499.56x = 689.61 × 388.77
  4. Step 4: Simplify right side
    499.56x = 268,099.68
  5. Step 5: Solve for x
    x = 268,099.68/499.56
  6. Step 6: Final answer
    x = 536.67

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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.