The numbers given in the problem above are part of an arithmetic sequence with first and sixth terms equal to -21 and -36, respectively. Firstly, calculate for the common difference (d).
d = (-36 - -21) / (6 - 1) = -3
The arithmetic mean is calculated by adding -3 to the term prior to it.
a2 = -21 + -3 = -24 a3 = -24 + -3 = -27
a4 = -27 + -3 = -30 a5 = -30 + -3 = -33
Thus the four arithmetic means are -24, -27, -30, and -33.
Multiplying eqn no. two with 4 we add it up with eqn 1.
When
So, x = - 10/17 and y = - 42/17.
Answer:
Sum of the first 15 terms = -405
Step-by-step explanation:
a + 3d = -15 (1)
a + 8d = -30 (2)
Where,
a = first term
d = common difference
n = number of terms
Subtract (1) from (1)
8d - 3d = -30 - (-15)
5d = -30 + 15
5d = -15
d = -15/5
= -3
d = -3
Substitute d = -3 into (1)
a + 3d = -15
a + 3(-3) = -15
a - 9 = -15
a = -15 + 9
a = -6
Sum of the first 15 terms
S = n/2[2a + (n − 1) × d]
= 15/2 {2×-6 + (15-1)-3}
= 7.5{-12 + (14)-3}
= 7.5{ -12 - 42}
= 7.5{-54}
= -405
Sum of the first 15 terms = -405
Answer:
300,000.
Step-by-step explanation:
6x10^-3 / 2x10^-8
= 3 x (10^(-3- (-8))
= 3 x 10^5
= 300,000
Answer:
3
Step-by-step explanation:
500 - 10 = 490
long way:
490 -135= 355
355 -135=220
220 -135=85
85 candy left
