Please help thanks so much!

You practice playing your guitar every day. You spend 15 minutes practicing chords and the rest of the time practicing a new son

Black_prince [1.1K]

Answer:

Step-by-step explanation:

Given that the total time taken to practice is given by the expression as

y=7(15+x)

Simplifying the expression we have

y=105+7x

Solving for x (that is making x subject of formula we have)

7x=y-105

Divide both sides by 7 we have

x=(y-105)/7

Therefore the expression is

x=(y-105)/7

5 0

3 years ago

The time, in seconds, required for an object accelerating at a constant rate of a meters/second to travel a distance of d meters

Serhud [2]

Answer:

$d=\dfrac{t^2}{a}$

Step-by-step explanation:

The time in seconds, required for an object accelerating at a constant rate of a meters/second to travel a distance of d meters is given by this equation.

t = va

We need to find the expression for d in terms of t and a.

As velocity = distance/time

$t=\dfrac{d}{t}a\\\\t^2=da\\\\d=\dfrac{t^2}{a}$

So, the distance d is $\dfrac{t^2}{a}$ .

8 0

3 years ago

In a class of 19 students, 3 are math majors. A group of four students is chosen at random. (Round your answers to four decimal

KatRina [158]

Answer:

(a) The probability is 0.4696

(b) The probability is 0.5304

(c) The probability is 0.0929

Step-by-step explanation:

The total number of ways in which we can select k elements from a group n elements is calculate as:

$nCx=\frac{n!}{x!(n-x)!}$

So, the number of ways in which we can select four students from a group of 19 students is:

$19C4=\frac{19!}{4!(19-4)!}=3,876$

On the other hand, the number of ways in which we can select four students with no math majors is:

$(16C4)*(3C0)=(\frac{16!}{4!(16-4)!})*(\frac{3!}{0!(3-0)!})=1820$

Because, we are going to select 4 students form the 16 students that aren't math majors and select 0 students from the 3 students that are majors.

At the same way, the number of ways in which we can select four students with one, two and three math majors are 1680, 360 and 16 respectively, and they are calculated as:

$(16C3)*(3C1)=(\frac{16!}{3!(16-3)!})*(\frac{3!}{1!(3-1)!})=1680$