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Finding the Fourth Proportional to 683.40, 943.05 and 388.71

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Solution

The fourth proportional to 683.40, 943.05 and 388.71 is: 536.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    683.40 : 943.05 = 388.71 : x
  2. Step 2: Convert to fraction form
    683.40/943.05 = 388.71/x
  3. Step 3: Cross multiply
    683.40x = 943.05 × 388.71
  4. Step 4: Simplify right side
    683.40x = 366,572.97
  5. Step 5: Solve for x
    x = 366,572.97/683.40
  6. Step 6: Final answer
    x = 536.40

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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.