Home / 778.89-1,075.08-691

Finding the Fourth Proportional to 778.89, 1,075.08 and 691

Calculator

Solution

The fourth proportional to 778.89, 1,075.08 and 691 is: 953.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    778.89 : 1,075.08 = 691 : x
  2. Step 2: Convert to fraction form
    778.89/1,075.08 = 691/x
  3. Step 3: Cross multiply
    778.89x = 1,075.08 × 691
  4. Step 4: Simplify right side
    778.89x = 742,880.28
  5. Step 5: Solve for x
    x = 742,880.28/778.89
  6. Step 6: Final answer
    x = 953.77

Related Problems

Find fourth proportional to 389.45, 537.54 and 345.50
Half scale
Find fourth proportional to 1,557.78, 2,150.16 and 1,382
Double scale
Find fourth proportional to 779.89, 1,076.46 and 692
Similar ratio
Find fourth proportional to 1,168.34, 1,612.62 and 1,036.50
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.