Home / 226.85-312.98-128.57

Finding the Fourth Proportional to 226.85, 312.98 and 128.57

Calculator

Solution

The fourth proportional to 226.85, 312.98 and 128.57 is: 177.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    226.85 : 312.98 = 128.57 : x
  2. Step 2: Convert to fraction form
    226.85/312.98 = 128.57/x
  3. Step 3: Cross multiply
    226.85x = 312.98 × 128.57
  4. Step 4: Simplify right side
    226.85x = 40,237.63
  5. Step 5: Solve for x
    x = 40,237.63/226.85
  6. Step 6: Final answer
    x = 177.38

Related Problems

Find fourth proportional to 113.42, 156.49 and 64.28
Half scale
Find fourth proportional to 453.69, 625.95 and 257.13
Double scale
Find fourth proportional to 227.85, 314.35 and 129.57
Similar ratio
Find fourth proportional to 340.27, 469.46 and 192.85
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.