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Finding the Fourth Proportional to 684.30, 945.64 and 518.20

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Solution

The fourth proportional to 684.30, 945.64 and 518.20 is: 716.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.30 : 945.64 = 518.20 : x
  2. Step 2: Convert to fraction form
    684.30/945.64 = 518.20/x
  3. Step 3: Cross multiply
    684.30x = 945.64 × 518.20
  4. Step 4: Simplify right side
    684.30x = 490,030.65
  5. Step 5: Solve for x
    x = 490,030.65/684.30
  6. Step 6: Final answer
    x = 716.10

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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.