Home / 1,312.88-1,984.19-1,290.20

Finding the Fourth Proportional to 1,312.88, 1,984.19 and 1,290.20

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Solution

The fourth proportional to 1,312.88, 1,984.19 and 1,290.20 is: 1,949.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,312.88 : 1,984.19 = 1,290.20 : x
  2. Step 2: Convert to fraction form
    1,312.88/1,984.19 = 1,290.20/x
  3. Step 3: Cross multiply
    1,312.88x = 1,984.19 × 1,290.20
  4. Step 4: Simplify right side
    1,312.88x = 2,559,985.57
  5. Step 5: Solve for x
    x = 2,559,985.57/1,312.88
  6. Step 6: Final answer
    x = 1,949.91

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.