Home / 1,390.20-2,075.26-1,288.86

Finding the Fourth Proportional to 1,390.20, 2,075.26 and 1,288.86

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Solution

The fourth proportional to 1,390.20, 2,075.26 and 1,288.86 is: 1,923.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,390.20 : 2,075.26 = 1,288.86 : x
  2. Step 2: Convert to fraction form
    1,390.20/2,075.26 = 1,288.86/x
  3. Step 3: Cross multiply
    1,390.20x = 2,075.26 × 1,288.86
  4. Step 4: Simplify right side
    1,390.20x = 2,674,719.60
  5. Step 5: Solve for x
    x = 2,674,719.60/1,390.20
  6. Step 6: Final answer
    x = 1,923.98

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1.5x scale

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.