Home / 71.51-108.21

Finding the Third Proportional to 71.51 and 108.21

Calculator

Solution

The third proportional to 71.51 and 108.21 is: 163.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.51 : 108.21 = 108.21 : x
  2. Step 2: Convert to fraction form
    71.51/108.21 = 108.21/x
  3. Step 3: Cross multiply
    71.51x = 108.21 × 108.21
  4. Step 4: Simplify right side
    71.51x = 11,709.61
  5. Step 5: Solve for x
    x = 11,709.61/71.51
  6. Step 6: Final answer
    x = 163.75

Related Problems

Find third proportional to 35.75 and 54.11
Half scale
Find third proportional to 143.02 and 216.42
Double scale
Find third proportional to 74 and 111
Similar ratio
Find third proportional to 107.26 and 162.32
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.