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Finding the Fourth Proportional to 720.90, 987.66 and 693.23

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Solution

The fourth proportional to 720.90, 987.66 and 693.23 is: 949.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.90 : 987.66 = 693.23 : x
  2. Step 2: Convert to fraction form
    720.90/987.66 = 693.23/x
  3. Step 3: Cross multiply
    720.90x = 987.66 × 693.23
  4. Step 4: Simplify right side
    720.90x = 684,670.60
  5. Step 5: Solve for x
    x = 684,670.60/720.90
  6. Step 6: Final answer
    x = 949.74

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.