Home / 117-128.50

Finding the Third Proportional to 117 and 128.50

Calculator

Solution

The third proportional to 117 and 128.50 is: 141.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    117 : 128.50 = 128.50 : x
  2. Step 2: Convert to fraction form
    117/128.50 = 128.50/x
  3. Step 3: Cross multiply
    117x = 128.50 × 128.50
  4. Step 4: Simplify right side
    117x = 16,512.25
  5. Step 5: Solve for x
    x = 16,512.25/117
  6. Step 6: Final answer
    x = 141.13

Related Problems

Find third proportional to 58.50 and 64.25
Half scale
Find third proportional to 234 and 257
Double scale
Find third proportional to 119 and 131
Similar ratio
Find third proportional to 175.50 and 192.75
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.10) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.