There are 12 blue marbles and 8 red marbles. find the probability of selecting one item

selecting one item? If you mean each color:

40% chance for a red marble / 2/5 chance

60% chance for a blue marble / 3/5 chance

Step-by-step explanation:

Because there are 12 blue marbles and 8 red marbles, we would total them to see how many marbles there are in total. There are 20 in total, but to find the probability, if we put all 20 marbles in a bag (blue and red), and we picked a marble at random, there are 8 red marbles and 12 blue marble in that bag. The probability that I will choose red marbles is 8/20 (or 8 red marbles out of 20 total marbles), and for blue marbles, it would be 12/20 (or 12 blue marbles out of 20 total marbles). Simplify both expression to 2/5, and 3/5 respectively. Finally, if you need percentage, just multiply the denominator by 5 to get it to a hundred, and do the same to the numerator. This way you don't change the value of the expression.

30 units^2

step-by-step explanation:

area is l × w

the length is 3

and the width is 10

3 × 10= 30 units squared

answer:   x = 3 + √11     and     x = 3 - √11

step-by-step explanation:

x² - 6x + 9 = 11

(x - 3)² = 11

x - 3 = ±√11

    x = 3 ± √11

x = 3 + √11     and     x = 3 - √11