Home / 1,686.40-2,326.08-1,391.20

Finding the Fourth Proportional to 1,686.40, 2,326.08 and 1,391.20

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Solution

The fourth proportional to 1,686.40, 2,326.08 and 1,391.20 is: 1,918.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,686.40 : 2,326.08 = 1,391.20 : x
  2. Step 2: Convert to fraction form
    1,686.40/2,326.08 = 1,391.20/x
  3. Step 3: Cross multiply
    1,686.40x = 2,326.08 × 1,391.20
  4. Step 4: Simplify right side
    1,686.40x = 3,236,042.50
  5. Step 5: Solve for x
    x = 3,236,042.50/1,686.40
  6. Step 6: Final answer
    x = 1,918.91

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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.