Home / 1,555.30-2,145.70-891.80

Finding the Fourth Proportional to 1,555.30, 2,145.70 and 891.80

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Solution

The fourth proportional to 1,555.30, 2,145.70 and 891.80 is: 1,230.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,555.30 : 2,145.70 = 891.80 : x
  2. Step 2: Convert to fraction form
    1,555.30/2,145.70 = 891.80/x
  3. Step 3: Cross multiply
    1,555.30x = 2,145.70 × 891.80
  4. Step 4: Simplify right side
    1,555.30x = 1,913,535.26
  5. Step 5: Solve for x
    x = 1,913,535.26/1,555.30
  6. Step 6: Final answer
    x = 1,230.33

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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.