Help please!!!(will mark brainliest)

Mathematics

1 answer:

Pani-rosa [81]2 years ago

5 0

Step-by-step explanation:

remember, a probability is always desired cases over total possible cases.

the class has 10+15 = 25 students.

and 5 of them will be picked as representatives to the school board.

how many total possibilities do we have ?

since picked students can be picked only once, and the sequence of the 5 picked students in the group does not matter, we have a combination without repetition :

C(25, 5) = 25! / (5! × (25-5)!) = 25! / (5! × 20!) =

= 25×24×23×22×21 / (5×4×3×2) =

= 5×1×23×22×21 = 53,130 possible outcomes.

how many desired outcomes ?

that would be how many options we have to pick 2 out of 10 and 3 out of 15 :

C(10,2) × C(15,3) = 10! / (2 × 8!) × 15! / (3! × 12!) =

= 10×9/2 × 15×14×13/(3×2) =

= 5×9 × 5×7×13 = 20,475 desired outcomes

and the probability is

20475 / 53130 = 4095 / 10626 = 1365 / 3542 = 195 / 506

= 0.385375494... ≈ 0.39

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Which inequality represents the sentence? The difference of seven and two tenths and a number is more than twenty nine. 7. 2 - n

Slav-nsk [51]

The inequality which represent, the difference of seven and two tenths and a number is more than twenty-nine, is

$7.2-n > 29$

<h3>What is the inequality equation?</h3>

Inequality equation is the equation in which the two expressions are compared with greater than, less than or other inequality signs.

Inequality is represented with the greater then(<), less then(>) or with the other inequity signs like less than equal to $\leq$ or greater than equal to $\geq$ .

Tenth is written as the fractional part of the number 10. The value of one tenth is equal to 1/10 or 0.1.

The sentence given for the inequality expression is, that the differences of seven and two tenths, and a number is more than twenty-nine.

The number seven and two tenths can be written as,

$7\dfrac{2}{10}$

Suppose the unknown number is n. Now, the differences of seven and two tenths, and this number (<em>n</em>) is more than twenty-nine. The more than word means, the greater than sign for equation. Thus, it can be expressed as,

$7\dfrac{2}{10}-n > 29\\\dfrac{72}{10}-n > 29\\7.2-n > 29$