Home / 1,560.40-2,153.36-861.78

Finding the Fourth Proportional to 1,560.40, 2,153.36 and 861.78

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Solution

The fourth proportional to 1,560.40, 2,153.36 and 861.78 is: 1,189.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,560.40 : 2,153.36 = 861.78 : x
  2. Step 2: Convert to fraction form
    1,560.40/2,153.36 = 861.78/x
  3. Step 3: Cross multiply
    1,560.40x = 2,153.36 × 861.78
  4. Step 4: Simplify right side
    1,560.40x = 1,855,722.58
  5. Step 5: Solve for x
    x = 1,855,722.58/1,560.40
  6. Step 6: Final answer
    x = 1,189.26

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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.