Home / 276.20-380.26-261.80

Finding the Fourth Proportional to 276.20, 380.26 and 261.80

Calculator

Solution

The fourth proportional to 276.20, 380.26 and 261.80 is: 360.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    276.20 : 380.26 = 261.80 : x
  2. Step 2: Convert to fraction form
    276.20/380.26 = 261.80/x
  3. Step 3: Cross multiply
    276.20x = 380.26 × 261.80
  4. Step 4: Simplify right side
    276.20x = 99,552.07
  5. Step 5: Solve for x
    x = 99,552.07/276.20
  6. Step 6: Final answer
    x = 360.43

Related Problems

Find fourth proportional to 138.10, 190.13 and 130.90
Half scale
Find fourth proportional to 552.40, 760.52 and 523.60
Double scale
Find fourth proportional to 277.20, 381.64 and 262.80
Similar ratio
Find fourth proportional to 414.30, 570.39 and 392.70
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.