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Finding the Fourth Proportional to 689.89, 946.42 and 669.08

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Solution

The fourth proportional to 689.89, 946.42 and 669.08 is: 917.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.89 : 946.42 = 669.08 : x
  2. Step 2: Convert to fraction form
    689.89/946.42 = 669.08/x
  3. Step 3: Cross multiply
    689.89x = 946.42 × 669.08
  4. Step 4: Simplify right side
    689.89x = 633,230.69
  5. Step 5: Solve for x
    x = 633,230.69/689.89
  6. Step 6: Final answer
    x = 917.87

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.