Home / 257-419.50

Finding the Third Proportional to 257 and 419.50

Calculator

Solution

The third proportional to 257 and 419.50 is: 684.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    257 : 419.50 = 419.50 : x
  2. Step 2: Convert to fraction form
    257/419.50 = 419.50/x
  3. Step 3: Cross multiply
    257x = 419.50 × 419.50
  4. Step 4: Simplify right side
    257x = 175,980.25
  5. Step 5: Solve for x
    x = 175,980.25/257
  6. Step 6: Final answer
    x = 684.75

Related Problems

Find third proportional to 128.50 and 209.75
Half scale
Find third proportional to 514 and 839
Double scale
Find third proportional to 259 and 423
Similar ratio
Find third proportional to 385.50 and 629.25
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.63) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.