Home / 1,680.40-2,320.08-1,238.80

Finding the Fourth Proportional to 1,680.40, 2,320.08 and 1,238.80

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Solution

The fourth proportional to 1,680.40, 2,320.08 and 1,238.80 is: 1,710.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,680.40 : 2,320.08 = 1,238.80 : x
  2. Step 2: Convert to fraction form
    1,680.40/2,320.08 = 1,238.80/x
  3. Step 3: Cross multiply
    1,680.40x = 2,320.08 × 1,238.80
  4. Step 4: Simplify right side
    1,680.40x = 2,874,115.10
  5. Step 5: Solve for x
    x = 2,874,115.10/1,680.40
  6. Step 6: Final answer
    x = 1,710.38

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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.