Home / 1,386.40-2,079.60-896.80

Finding the Fourth Proportional to 1,386.40, 2,079.60 and 896.80

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Solution

The fourth proportional to 1,386.40, 2,079.60 and 896.80 is: 1,345.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,386.40 : 2,079.60 = 896.80 : x
  2. Step 2: Convert to fraction form
    1,386.40/2,079.60 = 896.80/x
  3. Step 3: Cross multiply
    1,386.40x = 2,079.60 × 896.80
  4. Step 4: Simplify right side
    1,386.40x = 1,864,985.28
  5. Step 5: Solve for x
    x = 1,864,985.28/1,386.40
  6. Step 6: Final answer
    x = 1,345.20

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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.