Answer:
PE = 83 and Science = 71
Explanation:
let P represent PE and S represent Science with P > S, then
P + S = 154 → (1)
P - S = 12 → (2)
Adding the 2 equations term by term eliminates S
2P = 166 ( divide both sides by 2 )
P = 83
Substitute P = 83 into (1)
83 + S = 154 ( subtract 83 from both sides )
S = 71
Hence PE mark = 83 and Science mark = 71