Answer:
2.45
Step-by-step explanation:
B+16.12=18.57. Take the sum and the given value and subtract the given value from the sum. You can do this on all problems like this.
1. 3x-5<19
3x-5+5<19+5
3x<24
3x/3<24/3
x<8
2. -2x+12<-4
-2x+12-12<-4-12
-2x<-16
-2x/-2>-16/-2
x>8
3. Because the numbers are positive when divided.
4. The inequality sign is reversed because the 2nd to last step is divided by by a negative number. (This is also the same for multiplication)
5. -7d+8>29
-7d+8-8>29-8
-7d/7>21/-7
d>-3
6.12-3b<9
12-12-3b<9-12
-3b/-3>-3/-3
b>1
7.z/7-6=>-5
z/7-6+6=>-5+6
z/7*7=>1*7
z=>7 (what grade are you in?!)
From order of operations, we do multiply/divide first, then add/subtract. So:
(I assume that is 8 times 2, and 5 times x, solving for x)
6+8<span>⋅</span>2 = 5x
6 + 16 = 5x
22 = 5x
x = 22/5 (twenty two fifths)
Answer:
10 years
Step-by-step explanation:
the average or mean value is the sum of all data points divided by the number of data points.
x = the unknown age of the 5th student.
average = 9 = (5 + 7 + 8 + 15 + x)/5
45 = 5 + 7 + 8 + 15 + x = 35 + x
x = 45 - 35 = 10
the 5th student is 10 years old.