Isme estimated that there are 50 students in the seventh-grade class. There are actually 40 students in the seventh-grade class.
A. What is Isme's percent error?

B. Out of the 40 students in the seventh-grade, 60% of the students carry a cell phone. What fraction of the students in the seventh grade class carry a cell phone? How many students in the seventh grade class carry a cell phone/

A) 25%

B) fraction: ⅗

Number: 24

Step-by-step explanation:

Error: 50 - 40 = 10

%error = 10/40 × 100 = 25%

60% = 60/100 = ⅗

⅗ × 40 = 24

step-by-step explanation:

hello from mrbilldoesmath!

answer:

(7 x + 6 y) (49 x^2 - 42 x y + 36 y^2)

discussion:

the trick is to recognize that 343 = 7^3 and 216 = 6^3 and, in general,

a^3 + b^3 =   (a + b) (a^2 - a b + b^2).

in our case

343x^3+216y^3   =   (7x)^3 + (6y)^3

so take a = 7x and b = 6y in the above equation to get the answer.

you,

mrb