Answer: the length is 11 cm.
The width is 7 cm.
Step-by-step explanation:
Let L represent the length of the rectangular plastic box.
Let W represent the width of the rectangular plastic box.
The area of the rectangular top of the box is 77 square cm. This means that
LW = 77- - - - - - - ;- - - -1
The plastic box has a length 4 cm longer than its width. This means that
L = W + 4
Substituting L = W + 4 into equation 1, it becomes
(W + 4)W = 77
W² + 4W = 77
W² + 4W - 77 = 0
W² + 11W - 7W - 77 = 0
W(W + 11) - 7(W + 11) = 0
W - 7 = 0 or W + 11 = 0
W = 7 or W = - 11
Since the width cannot be negative, then W = 7cm
L = 77/7 = 11 cm
Answer:
it is at sea level because 0 meters above sea level indicates that it has not changed from sea level
Answer:
7.25
Step-by-step explanation:
Given :
___________ Sample size __ sample mean
Treatment 1 ____ 5 _______ 4
Treatment 2 ____ 10 ______ 8
Treatment 3 ____ 5 _______ 9
Sample size = (5 + 10 + 5). = 20
Overall mean = ((5*4). + (10*8) + (5*9)) / 20
Overall mean = (20 + 80 + 45) / 20
= 145 / 20
= 7.25
