Home / 317.80-438.78-207.56

Finding the Fourth Proportional to 317.80, 438.78 and 207.56

Calculator

Solution

The fourth proportional to 317.80, 438.78 and 207.56 is: 286.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    317.80 : 438.78 = 207.56 : x
  2. Step 2: Convert to fraction form
    317.80/438.78 = 207.56/x
  3. Step 3: Cross multiply
    317.80x = 438.78 × 207.56
  4. Step 4: Simplify right side
    317.80x = 91,073.18
  5. Step 5: Solve for x
    x = 91,073.18/317.80
  6. Step 6: Final answer
    x = 286.57

Related Problems

Find fourth proportional to 158.90, 219.39 and 103.78
Half scale
Find fourth proportional to 635.60, 877.56 and 415.12
Double scale
Find fourth proportional to 318.80, 440.16 and 208.56
Similar ratio
Find fourth proportional to 476.70, 658.17 and 311.34
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.