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Finding the Fourth Proportional to 499.79, 689.72 and 275.71

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Solution

The fourth proportional to 499.79, 689.72 and 275.71 is: 380.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.79 : 689.72 = 275.71 : x
  2. Step 2: Convert to fraction form
    499.79/689.72 = 275.71/x
  3. Step 3: Cross multiply
    499.79x = 689.72 × 275.71
  4. Step 4: Simplify right side
    499.79x = 190,162.70
  5. Step 5: Solve for x
    x = 190,162.70/499.79
  6. Step 6: Final answer
    x = 380.49

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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.