Home / 278-380

Finding the Third Proportional to 278 and 380

Calculator

Solution

The third proportional to 278 and 380 is: 519.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    278 : 380 = 380 : x
  2. Step 2: Convert to fraction form
    278/380 = 380/x
  3. Step 3: Cross multiply
    278x = 380 × 380
  4. Step 4: Simplify right side
    278x = 144,400
  5. Step 5: Solve for x
    x = 144,400/278
  6. Step 6: Final answer
    x = 519.42

Related Problems

Find third proportional to 139 and 190
Half scale
Find third proportional to 556 and 760
Double scale
Find third proportional to 280 and 383
Similar ratio
Find third proportional to 417 and 570
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.