Home / 217.91-326.65-80.86

Finding the Fourth Proportional to 217.91, 326.65 and 80.86

Calculator

Solution

The fourth proportional to 217.91, 326.65 and 80.86 is: 121.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    217.91 : 326.65 = 80.86 : x
  2. Step 2: Convert to fraction form
    217.91/326.65 = 80.86/x
  3. Step 3: Cross multiply
    217.91x = 326.65 × 80.86
  4. Step 4: Simplify right side
    217.91x = 26,410.88
  5. Step 5: Solve for x
    x = 26,410.88/217.91
  6. Step 6: Final answer
    x = 121.20

Related Problems

Find fourth proportional to 108.95, 163.32 and 40.43
Half scale
Find fourth proportional to 435.81, 653.29 and 161.71
Double scale
Find fourth proportional to 218.91, 328.14 and 81.86
Similar ratio
Find fourth proportional to 326.86, 489.97 and 121.28
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.