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Finding the Fourth Proportional to 684.82, 945.07 and 390.11

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Solution

The fourth proportional to 684.82, 945.07 and 390.11 is: 538.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.82 : 945.07 = 390.11 : x
  2. Step 2: Convert to fraction form
    684.82/945.07 = 390.11/x
  3. Step 3: Cross multiply
    684.82x = 945.07 × 390.11
  4. Step 4: Simplify right side
    684.82x = 368,677.51
  5. Step 5: Solve for x
    x = 368,677.51/684.82
  6. Step 6: Final answer
    x = 538.36

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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.