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Finding the Fourth Proportional to 690.80, 953.28 and 407.28

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Solution

The fourth proportional to 690.80, 953.28 and 407.28 is: 562.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.80 : 953.28 = 407.28 : x
  2. Step 2: Convert to fraction form
    690.80/953.28 = 407.28/x
  3. Step 3: Cross multiply
    690.80x = 953.28 × 407.28
  4. Step 4: Simplify right side
    690.80x = 388,251.88
  5. Step 5: Solve for x
    x = 388,251.88/690.80
  6. Step 6: Final answer
    x = 562.03

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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.