Answer:
She knit 4 pairs of socks and 11 pairs of gloves.
Explanation:
Let x be the number of pair of socks and y be the number pair of gloves she knit,
Since, she knit 15 pairs of socks and gloves,
⇒ x + y = 15 ------(1)
Also, she spent 89 hours in knitting in which she took 3 hours to knit a pair of socks and 7 hours to knit a pair of gloves,
⇒ 3x + 7y = 89 -----(2),
Equation (2) - 3 × Equation (1),
We get,
7y - 3y = 89 - 45
⇒ 4y = 44
Dividing both sides by 4,
⇒ y = 11,
From Equation (1),
x + 11 = 15
⇒ x = 15 - 11 = 4,
Hence, She knit 4 pairs of socks and 11 pairs of gloves.