Home / 1,285.60-1,928.40-1,123.60

Finding the Fourth Proportional to 1,285.60, 1,928.40 and 1,123.60

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Solution

The fourth proportional to 1,285.60, 1,928.40 and 1,123.60 is: 1,685.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.60 : 1,928.40 = 1,123.60 : x
  2. Step 2: Convert to fraction form
    1,285.60/1,928.40 = 1,123.60/x
  3. Step 3: Cross multiply
    1,285.60x = 1,928.40 × 1,123.60
  4. Step 4: Simplify right side
    1,285.60x = 2,166,750.24
  5. Step 5: Solve for x
    x = 2,166,750.24/1,285.60
  6. Step 6: Final answer
    x = 1,685.40

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Similar ratio
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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.