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Finding the Fourth Proportional to 643.41, 965.34 and 258.93

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Solution

The fourth proportional to 643.41, 965.34 and 258.93 is: 388.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.41 : 965.34 = 258.93 : x
  2. Step 2: Convert to fraction form
    643.41/965.34 = 258.93/x
  3. Step 3: Cross multiply
    643.41x = 965.34 × 258.93
  4. Step 4: Simplify right side
    643.41x = 249,955.49
  5. Step 5: Solve for x
    x = 249,955.49/643.41
  6. Step 6: Final answer
    x = 388.49

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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.