For simple interest, just multiply all of them together
note that 2% = 0.02
570(0.02)(4) = 45.6
simple interest is 45.6
oh and if you need the equation, it is p(r)t, or principle x rate x time
hope this helps
Answer:
Step-by-step explanation:
Present age of Barry = b
Present age of sister = s
Barry is 8 years older than his sister means if we subtract 8 from present age of Barry both will be of equal age
s=b-8 ............(1)
In 3 years means we have to add 3 in their present age
s+3=b+3
then
he will be twice as old as
2(s+3)=(b+3
2s+6=b+3
2s=b+3-6
2s=b-3...............(2)
Put the value of s from (1) to (2), we have
2(b-8)=b-3
2b-16=b-3
2b-b=-3+16
b=13
Put the value of b in (1)
s=13-8
s=5
Present age of Barry = b = 13
Present age of sister = s = 5
Answer:
Midpoint (-2,4)
distance nearest tenth = 8.9
The approximate distance = 9
Step-by-step explanation:
Formulas
PQ midpoint = (x2 + x1)/2, (y2 + y1)/2
distance d = sqrt( (x2 - x1)^2 + (y2 - y1)^2 )
Givens
x2 = -4
x1 = 0
y2 = 1
y1 = 7
Solution
M(PQ) = (-4+0)/2, (1 + 7)/2
M(PQ) = -2, 4
The midpoint is -2,4
The distance = sqrt( (4 - 0)^2 + (1 + 7)^2 )
The distance = sqrt(16 + 64)
The distance = sqrt(80)
The distance = 4√5 exactly
The distance = 8.94
The distance = 8.9 To the nearest tenth
Question 2
The distance is rounded to the nearest whole number which is 9.
Considering there is a function (relationship) and that it is linear, the distance will change proportionally to time constantly. In other words, we are taking the speed to be constant throughout the journey.
If we let:
t = time (min's) driving
d = distance (miles) from destination
Then we can represent the above information as:
t = 40: d = 59
t = 52: d = 50
If we think of this as a graph, we can think of the x-axis representing time and the y-axis representing the distance to the destination. Being linear, the function will be a line, i.e. it will have a constant gradient. If you were plot the two points inferred from the information and connect the two dots, you will get a declining line (one with a negative gradient) representing the inversely proportional relationship or equally, the negative correlation between the time driving and the distance to the destination. The equation of this line will be the linear function that relates time and the distance to the destination. To find this linear function, we do as follows:
Find the gradient (m) of the line:
m = Δy/Δx
In this case, the x-values are t-values and our y-values are d-values, so:
Δy = Δd
= 50 - 59
= -9
Δx = Δt
= 52 - 40
= 12
m = -9/12 = -3/4
Note: m is equivalent to speed with units: d/t
Use formula to find function and rearrange to give it in the desired format:
y - y₁ = m(x - x₁)
d - 50 = -3/4(t - 52)
4d - 200 = -3t + 156
4d + 3t - 356 = 0
Let t = 70 to find d at the time:
4d + 3(70) - 356 = 0
4d + 210 - 356 = 0
4d - 146 = 0
4d = 146
d = 73/2 = 36.5 miles
So after 70 min's of driving, Dale will be 36.5 miles from his destination.
Five times x plus seven equals eighteen
