Home / 169-257

Finding the Third Proportional to 169 and 257

Calculator

Solution

The third proportional to 169 and 257 is: 390.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    169 : 257 = 257 : x
  2. Step 2: Convert to fraction form
    169/257 = 257/x
  3. Step 3: Cross multiply
    169x = 257 × 257
  4. Step 4: Simplify right side
    169x = 66,049
  5. Step 5: Solve for x
    x = 66,049/169
  6. Step 6: Final answer
    x = 390.82

Related Problems

Find third proportional to 84.50 and 128.50
Half scale
Find third proportional to 338 and 514
Double scale
Find third proportional to 171 and 260
Similar ratio
Find third proportional to 253.50 and 385.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.52) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.