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Finding the Fourth Proportional to 642.25, 886.26 and 393.63

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Solution

The fourth proportional to 642.25, 886.26 and 393.63 is: 543.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.25 : 886.26 = 393.63 : x
  2. Step 2: Convert to fraction form
    642.25/886.26 = 393.63/x
  3. Step 3: Cross multiply
    642.25x = 886.26 × 393.63
  4. Step 4: Simplify right side
    642.25x = 348,858.52
  5. Step 5: Solve for x
    x = 348,858.52/642.25
  6. Step 6: Final answer
    x = 543.18

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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.