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Finding the Fourth Proportional to 642.22, 886.21 and 380.19

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Solution

The fourth proportional to 642.22, 886.21 and 380.19 is: 524.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.22 : 886.21 = 380.19 : x
  2. Step 2: Convert to fraction form
    642.22/886.21 = 380.19/x
  3. Step 3: Cross multiply
    642.22x = 886.21 × 380.19
  4. Step 4: Simplify right side
    642.22x = 336,928.18
  5. Step 5: Solve for x
    x = 336,928.18/642.22
  6. Step 6: Final answer
    x = 524.63

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Double scale
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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.