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Finding the Fourth Proportional to 689.07, 950.91 and 378.57

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Solution

The fourth proportional to 689.07, 950.91 and 378.57 is: 522.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.07 : 950.91 = 378.57 : x
  2. Step 2: Convert to fraction form
    689.07/950.91 = 378.57/x
  3. Step 3: Cross multiply
    689.07x = 950.91 × 378.57
  4. Step 4: Simplify right side
    689.07x = 359,986.00
  5. Step 5: Solve for x
    x = 359,986.00/689.07
  6. Step 6: Final answer
    x = 522.42

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Double scale
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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.