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Finding the Fourth Proportional to 685.60, 945.76 and 478.24

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Solution

The fourth proportional to 685.60, 945.76 and 478.24 is: 659.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.60 : 945.76 = 478.24 : x
  2. Step 2: Convert to fraction form
    685.60/945.76 = 478.24/x
  3. Step 3: Cross multiply
    685.60x = 945.76 × 478.24
  4. Step 4: Simplify right side
    685.60x = 452,300.26
  5. Step 5: Solve for x
    x = 452,300.26/685.60
  6. Step 6: Final answer
    x = 659.71

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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.