Answer:
2323
Step-by-step explanation:
Mental math means to find a way to do this problem in your head without using paper, pencil or a calculator.
The question says there are 23 classes and each class is to collect 101 items.
The equation would be 23 x 101.
To do this in your head real quick, make the numbers easier to multiply.
Make the 101 items 100. That means you are telling each class to collect 1 less item or 23 less items total.
You can do this in your head real quick. 23 classes collecting 100 items is 2300 items.
You had each class collect 100 items instead of 101. That mean you didn't collect 23 items. So if you add those back in, you will get
2323 items.
He will have enough money in his bank to avoid an insufficient fund charge because when you add 250+36.21+94.30 it equals 380.51. He had 386.49 in his account before he withdrawal that money, so he still had money in his account when he got money out.
The formula of an area of a rectangle:
A = wl
We have l = w - 4 and A = 21.
Substitute:
w(w - 4) = 21 <em>use distributive property</em>
(w)(w) + (w)(-4) = 21
w² - 4w = 21 <em>subtract 21 from both sides</em>
w² - 4w - 21 = 0
w² - 7w + 3w - 21 = 0
w(w - 7) + 3(w - 7) = 0
(w - 7)(w + 3) = 0 ↔ w - 7 = 0 ∨ w + 3 = 0
w = 7 ∨ w = -3 < 0
l = w - 4 → l = 7 - 4 = 3
<h3>Answer: the length = 3 u.</h3>
Your answer would be A)
Hope this helps (:
