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Finding the Fourth Proportional to 643.50, 964.53 and 319.05

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Solution

The fourth proportional to 643.50, 964.53 and 319.05 is: 478.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.50 : 964.53 = 319.05 : x
  2. Step 2: Convert to fraction form
    643.50/964.53 = 319.05/x
  3. Step 3: Cross multiply
    643.50x = 964.53 × 319.05
  4. Step 4: Simplify right side
    643.50x = 307,733.30
  5. Step 5: Solve for x
    x = 307,733.30/643.50
  6. Step 6: Final answer
    x = 478.22

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Double scale
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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.