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Finding the Fourth Proportional to 689.55, 951.58 and 394.80

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Solution

The fourth proportional to 689.55, 951.58 and 394.80 is: 544.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.55 : 951.58 = 394.80 : x
  2. Step 2: Convert to fraction form
    689.55/951.58 = 394.80/x
  3. Step 3: Cross multiply
    689.55x = 951.58 × 394.80
  4. Step 4: Simplify right side
    689.55x = 375,679.03
  5. Step 5: Solve for x
    x = 375,679.03/689.55
  6. Step 6: Final answer
    x = 544.82

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1.5x scale

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.