Home / 170.21-234.85-156.39

Finding the Fourth Proportional to 170.21, 234.85 and 156.39

Calculator

Solution

The fourth proportional to 170.21, 234.85 and 156.39 is: 215.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    170.21 : 234.85 = 156.39 : x
  2. Step 2: Convert to fraction form
    170.21/234.85 = 156.39/x
  3. Step 3: Cross multiply
    170.21x = 234.85 × 156.39
  4. Step 4: Simplify right side
    170.21x = 36,727.41
  5. Step 5: Solve for x
    x = 36,727.41/170.21
  6. Step 6: Final answer
    x = 215.78

Related Problems

Find fourth proportional to 85.11, 117.42 and 78.20
Half scale
Find fourth proportional to 340.42, 469.69 and 312.78
Double scale
Find fourth proportional to 171.21, 236.22 and 157.39
Similar ratio
Find fourth proportional to 255.32, 352.27 and 234.59
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.