Home / 242-390

Finding the Third Proportional to 242 and 390

Calculator

Solution

The third proportional to 242 and 390 is: 628.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    242 : 390 = 390 : x
  2. Step 2: Convert to fraction form
    242/390 = 390/x
  3. Step 3: Cross multiply
    242x = 390 × 390
  4. Step 4: Simplify right side
    242x = 152,100
  5. Step 5: Solve for x
    x = 152,100/242
  6. Step 6: Final answer
    x = 628.51

Related Problems

Find third proportional to 121 and 195
Half scale
Find third proportional to 484 and 780
Double scale
Find third proportional to 244 and 393
Similar ratio
Find third proportional to 363 and 585
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.61) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.