Home / 1,386.20-2,074.50-1,328.80

Finding the Fourth Proportional to 1,386.20, 2,074.50 and 1,328.80

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Solution

The fourth proportional to 1,386.20, 2,074.50 and 1,328.80 is: 1,988.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,386.20 : 2,074.50 = 1,328.80 : x
  2. Step 2: Convert to fraction form
    1,386.20/2,074.50 = 1,328.80/x
  3. Step 3: Cross multiply
    1,386.20x = 2,074.50 × 1,328.80
  4. Step 4: Simplify right side
    1,386.20x = 2,756,595.60
  5. Step 5: Solve for x
    x = 2,756,595.60/1,386.20
  6. Step 6: Final answer
    x = 1,988.60

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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.