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Finding the Fourth Proportional to 643.56, 964.70 and 259.08

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Solution

The fourth proportional to 643.56, 964.70 and 259.08 is: 388.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.56 : 964.70 = 259.08 : x
  2. Step 2: Convert to fraction form
    643.56/964.70 = 259.08/x
  3. Step 3: Cross multiply
    643.56x = 964.70 × 259.08
  4. Step 4: Simplify right side
    643.56x = 249,934.48
  5. Step 5: Solve for x
    x = 249,934.48/643.56
  6. Step 6: Final answer
    x = 388.36

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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.