Home / 21,321.30-31,940.39-12,980.63

Finding the Fourth Proportional to 21,321.30, 31,940.39 and 12,980.63

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Solution

The fourth proportional to 21,321.30, 31,940.39 and 12,980.63 is: 19,445.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,321.30 : 31,940.39 = 12,980.63 : x
  2. Step 2: Convert to fraction form
    21,321.30/31,940.39 = 12,980.63/x
  3. Step 3: Cross multiply
    21,321.30x = 31,940.39 × 12,980.63
  4. Step 4: Simplify right side
    21,321.30x = 414,606,319.74
  5. Step 5: Solve for x
    x = 414,606,319.74/21,321.30
  6. Step 6: Final answer
    x = 19,445.64

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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.