Home / 220.80-331.20-76.64

Finding the Fourth Proportional to 220.80, 331.20 and 76.64

Calculator

Solution

The fourth proportional to 220.80, 331.20 and 76.64 is: 114.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    220.80 : 331.20 = 76.64 : x
  2. Step 2: Convert to fraction form
    220.80/331.20 = 76.64/x
  3. Step 3: Cross multiply
    220.80x = 331.20 × 76.64
  4. Step 4: Simplify right side
    220.80x = 25,383.17
  5. Step 5: Solve for x
    x = 25,383.17/220.80
  6. Step 6: Final answer
    x = 114.96

Related Problems

Find fourth proportional to 110.40, 165.60 and 38.32
Half scale
Find fourth proportional to 441.60, 662.40 and 153.28
Double scale
Find fourth proportional to 221.80, 332.70 and 77.64
Similar ratio
Find fourth proportional to 331.20, 496.80 and 114.96
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.