Home / 901.80-1,243.80-621.54

Finding the Fourth Proportional to 901.80, 1,243.80 and 621.54

Calculator

Solution

The fourth proportional to 901.80, 1,243.80 and 621.54 is: 857.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    901.80 : 1,243.80 = 621.54 : x
  2. Step 2: Convert to fraction form
    901.80/1,243.80 = 621.54/x
  3. Step 3: Cross multiply
    901.80x = 1,243.80 × 621.54
  4. Step 4: Simplify right side
    901.80x = 773,071.45
  5. Step 5: Solve for x
    x = 773,071.45/901.80
  6. Step 6: Final answer
    x = 857.25

Related Problems

Find fourth proportional to 450.90, 621.90 and 310.77
Half scale
Find fourth proportional to 1,803.60, 2,487.60 and 1,243.08
Double scale
Find fourth proportional to 902.80, 1,245.18 and 622.54
Similar ratio
Find fourth proportional to 1,352.70, 1,865.70 and 932.31
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.