Home / 629.30-868.50-405.38

Finding the Fourth Proportional to 629.30, 868.50 and 405.38

Calculator

Solution

The fourth proportional to 629.30, 868.50 and 405.38 is: 559.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.30 : 868.50 = 405.38 : x
  2. Step 2: Convert to fraction form
    629.30/868.50 = 405.38/x
  3. Step 3: Cross multiply
    629.30x = 868.50 × 405.38
  4. Step 4: Simplify right side
    629.30x = 352,072.53
  5. Step 5: Solve for x
    x = 352,072.53/629.30
  6. Step 6: Final answer
    x = 559.47

Related Problems

Find fourth proportional to 314.65, 434.25 and 202.69
Half scale
Find fourth proportional to 1,258.60, 1,737 and 810.76
Double scale
Find fourth proportional to 630.30, 869.88 and 406.38
Similar ratio
Find fourth proportional to 943.95, 1,302.75 and 608.07
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.