Home / 107.28-161.06-85.64

Finding the Fourth Proportional to 107.28, 161.06 and 85.64

Calculator

Solution

The fourth proportional to 107.28, 161.06 and 85.64 is: 128.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    107.28 : 161.06 = 85.64 : x
  2. Step 2: Convert to fraction form
    107.28/161.06 = 85.64/x
  3. Step 3: Cross multiply
    107.28x = 161.06 × 85.64
  4. Step 4: Simplify right side
    107.28x = 13,793.18
  5. Step 5: Solve for x
    x = 13,793.18/107.28
  6. Step 6: Final answer
    x = 128.57

Related Problems

Find fourth proportional to 53.64, 80.53 and 42.82
Half scale
Find fourth proportional to 214.56, 322.12 and 171.28
Double scale
Find fourth proportional to 108.28, 162.56 and 86.64
Similar ratio
Find fourth proportional to 160.92, 241.59 and 128.46
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.