Answer: Hello There!................
Mean = Sum of observation / total number of observation
Mean = 1.35m
1.35 = Sum of length of 7 wood planks/ 7
1.35*7 = Sum of the length of 7 wood planks
9.45 = Sum of the length of 7 wood planks
Let the length of extra added wood plank = x
So,
(Sum of the length of 7 wood planks + x) / 8 = 1.4m
(9.45 + x) / 8 = 1.4
9.45 + x = 1.4 * 8
9.45 + x = 11.2
x = 11.2- 9.45
= 1.75
So,
The length of extra added wood plank = 1.75m
Step-by-step explanation:
Mark me brainest please. Hope this helps. Anna ♥
Answer:
50
Step-by-step explanation:
12x + 15 = 5x + 85 {Subtract 15 from both sides}
12x + 15 - 15 = 5x + 85 - 15
12x = 5x + 70 {Subtract 5x from both sides}
12x - 5x = 70
7x = 70 {Divide both sides by 7}
x = 70/7
x = 10
∠U = 5x = 5*10 = 50
$27 x 18 students = 486 actual cost.
$30 x 10 students = 300 estimated total cost using compatible numbers.
$20 x 20 students = 400 estimated total cost using compatible numbers. (better option because it is nearer to the actual cost)
Compatible numbers are numbers that can easily be multiplied or divided using mental computation.
Compatible number for 27 and 18 can be: 30 and 20 OR 20 and 20 OR 30 and 10 OR 20 and 10.
However, there is a rule in multiplying the compatible numbers, when one number is increased the other number must be decreased.
So 27 can be increased to 30; while 18 can be decreased to 10 to get a product of 300.
27 can be decreased to 20; while 18 can be increased to 20 to get a product of 400.
Answer:
D. 63
Step-by-step explanation:
It has more than two factors. (composite)
C. 7/8 is larger than 1/5