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Finding the Fourth Proportional to 643.96, 888.48 and 378.28

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Solution

The fourth proportional to 643.96, 888.48 and 378.28 is: 521.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.96 : 888.48 = 378.28 : x
  2. Step 2: Convert to fraction form
    643.96/888.48 = 378.28/x
  3. Step 3: Cross multiply
    643.96x = 888.48 × 378.28
  4. Step 4: Simplify right side
    643.96x = 336,094.21
  5. Step 5: Solve for x
    x = 336,094.21/643.96
  6. Step 6: Final answer
    x = 521.92

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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.