Answer: $2,324
Explanation:
Let his salary be x.
He spent 1/4 of his salary, or x/4, and 1/7 of his salary, or x/7.
His salary was x. He spent x/4 and x/7, so we subtract those two amounts from his salary.
x - x/4 - x/7 is the amount he still has. He still has $1411. We equate the two and have an equation.
x - x/4 - x/7 = 1411
x/1 - x/4 - x/7 = 1411
We need to combine the three fractions on the left side, so we need to use a common denominator. The least common multiple of 1, 4, and 7 is 28, so 28 is the LCD.
28x/28 - 7x/28- 4x/28= 1411
17x/28= 1411
Multiply both sides by 28.
17x = 39,508
Divide both sides by 17.
x = 2,324
Check:
1/4 of his salary is 2,324/4 = 581
1/7 of his salary is 2,324/7 = 332
Now we subtract 581 and 332 from 2,324
2324 - 581 - 332 = 1411 which is what the problem stated.
Our answer $2,324 is correct.