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Finding the Fourth Proportional to 680.25, 938.69 and 381.51

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Solution

The fourth proportional to 680.25, 938.69 and 381.51 is: 526.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.25 : 938.69 = 381.51 : x
  2. Step 2: Convert to fraction form
    680.25/938.69 = 381.51/x
  3. Step 3: Cross multiply
    680.25x = 938.69 × 381.51
  4. Step 4: Simplify right side
    680.25x = 358,119.15
  5. Step 5: Solve for x
    x = 358,119.15/680.25
  6. Step 6: Final answer
    x = 526.45

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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.