Answer:
He should have to spell at least 36 of these words correctly.
Step-by-step explanation:
40 words.
He must spell at least 90% of those words correctly.
At least how many words should he have to spell correctly to get the prize?
90% of 40. So
0.9*40 = 4*9 = 36
He should have to spell at least 36 of these words correctly.
Answer:
25m
Step-by-step explanation:
Shannon's rate is 2,500m/100min. Simplifying, we see that this is equal to 25m/1min.
So, she walks 25 m in one minute.
Answer:
Option (1)
Step-by-step explanation:
x -2 -1 0 1 2
y 10 2.5 0 2.5 3.0
Ist difference,




= -2.5


= 2.5


= 7.5
2nd difference,


= 5


= 5


= 5
Since 2nd difference is common, given table represents a quadratic equation.
Let the equation is,
y = ax²+ bx + c
For a point (0, 0) passing through the quadratic equation,
0 = c
Therefore, quadratic equation is y = ax² + bx
Since ordered pair (-1, 2.5) passes through the graph of the function,
2.5 = a(-1)² + b(-1)
a - b = 2.5 ------(1)
For another point (1, 2.5)
2.5 = a(1)² + b(1)
a + b = 2.5 ------(2)
By adding equations (1) and (2),
2a = 5
a = 2.5
and from equation (2)→ y = 0
Therefore, equation of the quadratic function given in the table is y = 2.5x²
Option (1) is the answer.