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Finding the Fourth Proportional to 690.80, 947.44 and 655.61

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Solution

The fourth proportional to 690.80, 947.44 and 655.61 is: 899.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.80 : 947.44 = 655.61 : x
  2. Step 2: Convert to fraction form
    690.80/947.44 = 655.61/x
  3. Step 3: Cross multiply
    690.80x = 947.44 × 655.61
  4. Step 4: Simplify right side
    690.80x = 621,151.14
  5. Step 5: Solve for x
    x = 621,151.14/690.80
  6. Step 6: Final answer
    x = 899.18

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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.