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Finding the Fourth Proportional to 1,321.61, 1,980.93 and 627.71

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Solution

The fourth proportional to 1,321.61, 1,980.93 and 627.71 is: 940.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,321.61 : 1,980.93 = 627.71 : x
  2. Step 2: Convert to fraction form
    1,321.61/1,980.93 = 627.71/x
  3. Step 3: Cross multiply
    1,321.61x = 1,980.93 × 627.71
  4. Step 4: Simplify right side
    1,321.61x = 1,243,449.57
  5. Step 5: Solve for x
    x = 1,243,449.57/1,321.61
  6. Step 6: Final answer
    x = 940.86

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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.