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Finding the Fourth Proportional to 690.90, 953.44 and 380.40

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Solution

The fourth proportional to 690.90, 953.44 and 380.40 is: 524.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.90 : 953.44 = 380.40 : x
  2. Step 2: Convert to fraction form
    690.90/953.44 = 380.40/x
  3. Step 3: Cross multiply
    690.90x = 953.44 × 380.40
  4. Step 4: Simplify right side
    690.90x = 362,686.19
  5. Step 5: Solve for x
    x = 362,686.19/690.90
  6. Step 6: Final answer
    x = 524.95

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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.