Home / 317.31-438-307.05

Finding the Fourth Proportional to 317.31, 438 and 307.05

Calculator

Solution

The fourth proportional to 317.31, 438 and 307.05 is: 423.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    317.31 : 438 = 307.05 : x
  2. Step 2: Convert to fraction form
    317.31/438 = 307.05/x
  3. Step 3: Cross multiply
    317.31x = 438 × 307.05
  4. Step 4: Simplify right side
    317.31x = 134,487.90
  5. Step 5: Solve for x
    x = 134,487.90/317.31
  6. Step 6: Final answer
    x = 423.84

Related Problems

Find fourth proportional to 158.66, 219 and 153.53
Half scale
Find fourth proportional to 634.62, 876 and 614.10
Double scale
Find fourth proportional to 318.31, 439.38 and 308.05
Similar ratio
Find fourth proportional to 475.97, 657 and 460.58
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.