You have to formulate equations for this problem.
Let S = Science score
M = Math score
C =
Chemistry score
To illustrate the given:
0.9S = 0.75M
0.9S = 0.8C
You are given that Karen’s Math score is 96 marks. You have
to substitute the Math score to the first equation.
0.9S = 0.75(96)
0.9S = 72
S = 80
Therefore, Karen’s Science score is 80. Now, you have to
substitute the Science score to the second equation.
0.9(80) = 0.8C
0.8C = 72
C = 90
So, Karen’s Chemistry score is 90.
Therefore, the total score of the 3 subjects is 266 (96 + 80
+ 90).
Answer:
Mr mehra's salary is 26250
Step-by-step explanation:
suppose,
Mr mehra's salary is x
so,
He spends in food = 30% of x
=(30/100) . x [x%=x/100]
= 30x/100
=3x/10
He spends in charity =10% of x
=10x/100
=x/10
Money left = 15750
so,
x = 3x/10 + x/10 + 15750
⇒x - 3x/10 - x/10 = 15750
⇒(10x-3x-x) /10 = 15750
⇒6x/10 = 15750
⇒6x=157500
⇒x = 157500/6
⇒x = 26250
∴Mr mehra's salary is 26250
If there are no restrictions, there can be;
6 ways x 6 ways x 6 ways x 6 ways x 6 ways x 6 ways = 6^6 ways for the letters a, b, c, d, e and f to be arranged.
However, if you want to arrange them so that each letter is used only once;
6 ways x 5 ways x 4 ways x 3 ways x 2 ways x 1 way = 6! ways
Hope I helped :)
AF = AC + CF
AF = (5x - 16) + (2x - 4)
AF = 5x - 16 + 2x - 4
AF = 7x - 20
