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Finding the Fourth Proportional to 642.18, 886.23 and 380.19

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Solution

The fourth proportional to 642.18, 886.23 and 380.19 is: 524.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.18 : 886.23 = 380.19 : x
  2. Step 2: Convert to fraction form
    642.18/886.23 = 380.19/x
  3. Step 3: Cross multiply
    642.18x = 886.23 × 380.19
  4. Step 4: Simplify right side
    642.18x = 336,935.78
  5. Step 5: Solve for x
    x = 336,935.78/642.18
  6. Step 6: Final answer
    x = 524.67

Related Problems

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Half scale
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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.