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Finding the Fourth Proportional to 638.40, 957.72 and 253.44

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Solution

The fourth proportional to 638.40, 957.72 and 253.44 is: 380.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.40 : 957.72 = 253.44 : x
  2. Step 2: Convert to fraction form
    638.40/957.72 = 253.44/x
  3. Step 3: Cross multiply
    638.40x = 957.72 × 253.44
  4. Step 4: Simplify right side
    638.40x = 242,724.56
  5. Step 5: Solve for x
    x = 242,724.56/638.40
  6. Step 6: Final answer
    x = 380.21

Related Problems

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Half scale
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Double scale
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Similar ratio
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.