Answer:
The answer in interval notation is ( 73 , 100 )
Step-by-step explanation:
If we call x and y the lower and upper values for David to get an average of 80 and 89 respectively, we can calculate these two values solving a pair of equations:
(81 + 92 + 74 + x ) / 4 = 80 ⇒ (247 + x )/4 = 80
247 + x = 320 ⇒ x = 320 - 247
x = 73
And
(81 + 92 + 74 + y ) / 4 = 89 ⇒ ( 247 + y ) / 4 = 89
247 + y = 356
y = 356 - 247
y = 109
But tests are a 100-point test
Then the answer in interval notation is ( 73 , 100 )
Answer:
25
Step-by-step explanation:
The pattern is + 1, + 3, + 6,... i.e. + 1, + (1 + 2), + (1 + 2 + 3),...
.'. Missing number = 15 + (1 + 2 + 3 + 4) = 25.
Answer:
8 ≤ x
Step-by-step explanation:
6(2 − 6x) ≤ 4 − 35x
Expand bracket;
12 - 36x ≤ 4 − 35x
Add 36x to both sides to get;
12 ≤ 4 + x
Subtract 4 from both sides to get;
8 ≤ x
Answer:
320 i think
Step-by-step explanation:
