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Finding the Fourth Proportional to 689.99, 951.80 and 479.79

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Solution

The fourth proportional to 689.99, 951.80 and 479.79 is: 661.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.99 : 951.80 = 479.79 : x
  2. Step 2: Convert to fraction form
    689.99/951.80 = 479.79/x
  3. Step 3: Cross multiply
    689.99x = 951.80 × 479.79
  4. Step 4: Simplify right side
    689.99x = 456,661.72
  5. Step 5: Solve for x
    x = 456,661.72/689.99
  6. Step 6: Final answer
    x = 661.84

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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.