Home / 158.62-218.64-121.72

Finding the Fourth Proportional to 158.62, 218.64 and 121.72

Calculator

Solution

The fourth proportional to 158.62, 218.64 and 121.72 is: 167.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    158.62 : 218.64 = 121.72 : x
  2. Step 2: Convert to fraction form
    158.62/218.64 = 121.72/x
  3. Step 3: Cross multiply
    158.62x = 218.64 × 121.72
  4. Step 4: Simplify right side
    158.62x = 26,612.86
  5. Step 5: Solve for x
    x = 26,612.86/158.62
  6. Step 6: Final answer
    x = 167.78

Related Problems

Find fourth proportional to 79.31, 109.32 and 60.86
Half scale
Find fourth proportional to 317.24, 437.28 and 243.44
Double scale
Find fourth proportional to 159.62, 220.02 and 122.72
Similar ratio
Find fourth proportional to 237.93, 327.96 and 182.58
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.