Answer:
Step-by-step explanation:
a1 = 3(1) - 7 = - 4
a2 = 3(2) - 7 = -1
d = a2 - a1
d = -1 - (-4)
d = -1 + 4
d = 3
a60 = 3(60) - 7
a60 = 180 - 7
a60 = 173
n = 60
Sum = (a1 + a60) * n / 2
Sum = (-4 + 173) * 60/2
Sum = (169)*30
Sum = 5070
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Just to check, we'll use the second summation formula
d = 3
n = 60
a1 = -4
Sum = (2*a1 + (n - 1)*d )*n / 2
Sum = (2*(-4) + (60 -1)*3)* 60/2
Sum = (-8 + 59*3) * 30
Sum = (177 - 8)*30
Sum = 169 * 30
Sum = 5070
Same answer.
Answer:
2/7
Step-by-step explanation:
You do the number it goes up, 1 to 3 in this case, over the number it goes sideways, 3 to -4. My teacher always said rise over run to help us remember.
Answer:
Step-by-step explanation:
.30 x p = ___
p - ___ = price of shoes after the discount
Answer:
it either can be 3:6 or 6:3 but I think its 3:6