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Finding the Fourth Proportional to 720.98, 993.69 and 621.15

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Solution

The fourth proportional to 720.98, 993.69 and 621.15 is: 856.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.98 : 993.69 = 621.15 : x
  2. Step 2: Convert to fraction form
    720.98/993.69 = 621.15/x
  3. Step 3: Cross multiply
    720.98x = 993.69 × 621.15
  4. Step 4: Simplify right side
    720.98x = 617,230.54
  5. Step 5: Solve for x
    x = 617,230.54/720.98
  6. Step 6: Final answer
    x = 856.11

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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.