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Finding the Fourth Proportional to 2,185.78, 3,278.70 and 646.78

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Solution

The fourth proportional to 2,185.78, 3,278.70 and 646.78 is: 970.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,185.78 : 3,278.70 = 646.78 : x
  2. Step 2: Convert to fraction form
    2,185.78/3,278.70 = 646.78/x
  3. Step 3: Cross multiply
    2,185.78x = 3,278.70 × 646.78
  4. Step 4: Simplify right side
    2,185.78x = 2,120,597.59
  5. Step 5: Solve for x
    x = 2,120,597.59/2,185.78
  6. Step 6: Final answer
    x = 970.18

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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.