D=2n
.05n+.1d=3.5
I multiplied the nickels and dimes by these values because that is their actual monetary value
.05n=3.5-.1d
multiply everything by 20
n=70-2d
d/2=70-2d
.5d+2d=70
2.5d=70
d=28
n=14
so there are <u>28 dimes and 14 nickels
</u>checking this answer
28 dimes = $2.8
14 nickels = .70
2.8+.7=3.5
Hello :
the common ratio is r = -95-(-100)=5
the general terme is : un= u1+(n-1)r
un = -100 +(n-1)(5)
un =-100 +5n-5
un = 5n-105
The last term is : 100
un =100
5n-105 = 100
5n =205
n = 41 (Number of terms)
The last term is : u 41
<span>the sum is : S= (41/2)(-100+100)=0</span>
We must multiply and divide before adding and subtracting here. Working from left to right, we get:
8 + 15 - 5 = ?
8 + 10 = ?
18 (answer)