Home / 115-212

Finding the Third Proportional to 115 and 212

Calculator

Solution

The third proportional to 115 and 212 is: 390.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    115 : 212 = 212 : x
  2. Step 2: Convert to fraction form
    115/212 = 212/x
  3. Step 3: Cross multiply
    115x = 212 × 212
  4. Step 4: Simplify right side
    115x = 44,944
  5. Step 5: Solve for x
    x = 44,944/115
  6. Step 6: Final answer
    x = 390.82

Related Problems

Find third proportional to 57.50 and 106
Half scale
Find third proportional to 230 and 424
Double scale
Find third proportional to 117 and 216
Similar ratio
Find third proportional to 172.50 and 318
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.84) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.