Answer:
40
Step-by-step explanation: 40 x .45 = 18
Answer:
100
Step-by-step explanation:
We have the sum of first n terms of an AP,
Sn = n/2 [2a+(n−1)d]
Given,
36= 6/2 [2a+(6−1)d]
12=2a+5d ---------(1)
256= 16/2 [2a+(16−1)d]
32=2a+15d ---------(2)
Subtracting, (1) from (2)
32−12=2a+15d−(2a+5d)
20=10d ⟹d=2
Substituting for d in (1),
12=2a+5(2)=2(a+5)
6=a+5 ⟹a=1
∴ The sum of first 10 terms of an AP,
S10 = 10/2 [2(1)+(10−1)2]
S10 =5[2+18]
S10 =100
This is the sum of the first 10 terms.
Hope it will help.
The mean of n numbers is the sum of the numbers divided by n.
You have a mean score of 84 after taking 5 tests. Let x be the sum of scores.
You scored a total of 420 points on five tests.
You need to have a mean score of 85 after taking 6 tests. Let y be the score you need to obtain. Your total score on 6 tests is 420+y.
You need to score 90 points on the sixth test.
at most is either that number or less
so x<=72 would be the inequality
We have to prove that is irrational. We can prove this statement by contradiction.
Let us assume that is a rational number. Therefore, we can express:
Let us represent this equation as:
Upon squaring both the sides:
Since a has been assumed to be rational, therefore, must as well be rational.
But we know that is irrational, therefore, from equation the expression must be irrational, which contradicts with our claim.
Therefore, by contradiction, is irrational.