A positive number when decreased by 4 is equal to 21 times the reciprocal of the number.
A positive number when decreased by 4 is equal to 21 times the reciprocal of the number. The number is
Answer/Solution
7
Steps/Work
Sol.
Let the numbers be x.
Then, x - 4 = 21/x
⇔ x2 - 4x - 21 = 0
⇔ (x-7)(x+3) = 0
⇔ x = 7.
Answer C
Let the numbers be x.
Then, x - 4 = 21/x
⇔ x2 - 4x - 21 = 0
⇔ (x-7)(x+3) = 0
⇔ x = 7.
Answer C