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Finding the Fourth Proportional to 720.27, 993.98 and 421.45

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Solution

The fourth proportional to 720.27, 993.98 and 421.45 is: 581.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.27 : 993.98 = 421.45 : x
  2. Step 2: Convert to fraction form
    720.27/993.98 = 421.45/x
  3. Step 3: Cross multiply
    720.27x = 993.98 × 421.45
  4. Step 4: Simplify right side
    720.27x = 418,908.80
  5. Step 5: Solve for x
    x = 418,908.80/720.27
  6. Step 6: Final answer
    x = 581.60

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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.