[Find the changes in the salary]
Increase = 28100 - 25300 = 2800
[the change, divided by the original amount. x100 to give the percentage]
percentage increase = 2800/25300 x 100 = 11.07%
X+x+20+2x=180
4x+20=180
4x=160
x=40
Answer:
Step-by-step explanation:
From the information given,
Mark: 6,7,8,9,10
frequency:5,4,7,10,4
a) Range = highest mark - lowest mark
Range = 10 - 6 = 4
b) The number of students in the group is the sum of the frequency. Therefore,
Number of students = 5 + 4 + 7 + 10 + 4 = 30 students
c) Mean mark = (mark × frequency)/total frequency
[(6 × 5) + (7 × 4) + (8 × 7) + (9 × 10) + 10 × 4)]/ 30
Mean mark = (30 + 28 + 56 + 90 + 40)/30 = 244/30
Mean mark = 8.1
Answer:
try x equals nine I am sure
Answer:
height = 12 cm
base length = 4 cm
Step-by-step explanation:
area of a triangle
base length × height / 2
x = height
y = base length
x = y + 8
24 = y × (y + 8) / 2
48 = y × (y + 8) = y² + 8y
squared equation
y² + 8y - 48 = 0
solution
y = (-b ± sqrt(b² - 4ac))/(2a)
a = 1
b = 8
c = -48
y = (-8 ± sqrt(64 - 4×-48))/2 = (-8 ± sqrt(64 + 192))/2 =
= (-8 ± sqrt(256))/2 = (-8 ± 16)/2 = -4 ± 8
y1 = -4 + 8 = 4 cm
y2 = -4 - 8 = -12
but a negative base length did not make any sense, so only y = 4 remains.
x = y + 8 = 4 + 8 = 12 cm