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Finding the Fourth Proportional to 620.16, 856.92 and 490.20

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Solution

The fourth proportional to 620.16, 856.92 and 490.20 is: 677.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.16 : 856.92 = 490.20 : x
  2. Step 2: Convert to fraction form
    620.16/856.92 = 490.20/x
  3. Step 3: Cross multiply
    620.16x = 856.92 × 490.20
  4. Step 4: Simplify right side
    620.16x = 420,062.18
  5. Step 5: Solve for x
    x = 420,062.18/620.16
  6. Step 6: Final answer
    x = 677.34

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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.