Home / 316-428

Finding the Third Proportional to 316 and 428

Calculator

Solution

The third proportional to 316 and 428 is: 579.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    316 : 428 = 428 : x
  2. Step 2: Convert to fraction form
    316/428 = 428/x
  3. Step 3: Cross multiply
    316x = 428 × 428
  4. Step 4: Simplify right side
    316x = 183,184
  5. Step 5: Solve for x
    x = 183,184/316
  6. Step 6: Final answer
    x = 579.70

Related Problems

Find third proportional to 158 and 214
Half scale
Find third proportional to 632 and 856
Double scale
Find third proportional to 318 and 431
Similar ratio
Find third proportional to 474 and 642
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.