Solution-
First 9 letters of alphabet are- A,B,C,D,E,F,G,H,I
Total number of ways of selection of 4 letters from 9 alphabets = 9C4
=9!÷((4!).(9-4)!) = 9!÷(4!×5!) = (9×8×7×6)÷(24) = 126
The number of ways of arranging these 4 numbers = 4! = 24
∴ Total number of possible permutations = 9C4×4! = 126×24 = 3024
∴ option number 2 is correct.
Answer:
14 days
Step-by-step explanation:
Total Problems = 175
Finished Problems = 8
Remaining = 175 - 8 = 167
8 problems in 30 minutes, means:
30/8 = 15/4 = 3.75 minutes per problem
If he works for 45 minutes, at that rate, he can solve:
45/3.75 = 12 problems per day
To finish 167 problems, he will need:
167/12 = 13.91
Rounded, that is <u>14 days more to finish</u>
Answer:
the answer is
Step-by-step explanation:
x=1/2y+5---i
4x+3y=-20 ----ii
putting value of x in eqn Ii
4×(1/2×y+5)+3y=-20
2y+5+3y=-20
5y+5=-20
5y=-20-5
5y=-25
y=-25/5
y=-5
putting value in eqn I
x=1/2×-5+5
x=-5/2+5
x=5/2
Answer:b
Step-by-step explanation:
