Home / 2,128.85-2,937.87-1,289.70

Finding the Fourth Proportional to 2,128.85, 2,937.87 and 1,289.70

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Solution

The fourth proportional to 2,128.85, 2,937.87 and 1,289.70 is: 1,779.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,128.85 : 2,937.87 = 1,289.70 : x
  2. Step 2: Convert to fraction form
    2,128.85/2,937.87 = 1,289.70/x
  3. Step 3: Cross multiply
    2,128.85x = 2,937.87 × 1,289.70
  4. Step 4: Simplify right side
    2,128.85x = 3,788,970.94
  5. Step 5: Solve for x
    x = 3,788,970.94/2,128.85
  6. Step 6: Final answer
    x = 1,779.82

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.