Answer:
3x + 10cm
Step-by-step explanation:
This is calculated as:
Length of Tom's pencil - Length is Ellen's pencil
Length of Tom's pencil: 5x+25cm long.
Length of Ellen's pencil : 2x+15cm long.
(5x + 25)cm - (2x + 15)cm
5x + 25 - 2x - 15
5x - 2x + 25 - 15
3x + 10 cm
Therefore, Tom's pencil is 3x + 10cm longer is than Ellen's.
This expression is a difference of squares:

Answer:
3/10 of the aquarium are yellow tangs.
Step-by-step explanation:
Given that in an aquarium 2/5 of the fish or surgeonfish and of these, 3/4 are yellow tangs, to determine what fraction of all fish in the aquarium are yellow tangs the following calculation must be performed:
2/5 = 0.40
0.40 x 3/4 = X
1.20 / 4 = X
0.30 = X
0.30 = 3/10
Therefore 3/10 of the aquarium are yellow tangs.
32 but make sure it’s emedicpend PAS