Home / 1,289.64-1,918.95-1,285.32

Finding the Fourth Proportional to 1,289.64, 1,918.95 and 1,285.32

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Solution

The fourth proportional to 1,289.64, 1,918.95 and 1,285.32 is: 1,912.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.64 : 1,918.95 = 1,285.32 : x
  2. Step 2: Convert to fraction form
    1,289.64/1,918.95 = 1,285.32/x
  3. Step 3: Cross multiply
    1,289.64x = 1,918.95 × 1,285.32
  4. Step 4: Simplify right side
    1,289.64x = 2,466,464.81
  5. Step 5: Solve for x
    x = 2,466,464.81/1,289.64
  6. Step 6: Final answer
    x = 1,912.52

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.