On a test, the marks for ten students are: 2 students, 85%; 4 students, 78%; 3 students, 66%; and 1 student, 92%. What is the average mark on the test? (Exact
Answer)

77.2%

Step-by-step explanation:

The average formula is:

Let's first find the sum of all the numbers (remember sum means to add):

(2)(85) + (4)(78) + (3)(66) + 92 = ?

170 + 312 + 198 + 92 = 772

There are marks for 10 students so that is what goes at the bottom (10 students, 10 test scores)

Plug both things into the equation:

Therefore, the average mark on the test was 77.2%

Hope this helps!!

- Kay :)

d) 30 units^2

area of rectangle = l × b

we know,

length = 10 unit

breadth = 3 unit

applying the formula,

= l × b

= 10 × 3

= 30 unit^2

happy to

pls mark as brainliest

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.