Answer please show steps please

Mathematics

1 answer:

erik [133]3 years ago

6 0

Answer:

25 girls

Step-by-step explanation:

Let

x denote number of boys

and

y denote number of girls

According to the statement that total 45 people came,

x+y = 45 => Eqn 1

And total paid amount was 175

So,

5x + 3y = 175 => Eqn 2

For solving, We will use the substitution method

So, from eqn 1

x = 45-y

Putting value of x in eqn 2

5(45-y) +3y = 175

225 - 5y + 3y = 175

-2y+225 = 175

-2y = 175-225

-2y = -50

2y = 50

y = 25

Putting y =25 in eqn 1

x+25 = 45

x = 45 - 25

x = 20

As y= 25

So, 25 girls came to the dance ..

You might be interested in

Evaluate the surface integral S F · dS for the given vector field F and the oriented surface S. In other words, find the flux of

Tomtit [17]

Apparently my answer was unclear the first time?

The flux of F across S is given by the surface integral,

$\displaystyle\iint_S\mathbf F\cdot\mathrm d\mathbf S$

Parameterize S by the vector-valued function r(u, v) defined by

$\mathbf r(u,v)=7\cos u\sin v\,\mathbf i+7\sin u\sin v\,\mathbf j+7\cos v\,\mathbf k$

with 0 ≤ u ≤ π/2 and 0 ≤ v ≤ π/2. Then the surface element is

dS = n • dS

where n is the normal vector to the surface. Take it to be

$\mathbf n=\dfrac{\frac{\partial\mathbf r}{\partial v}\times\frac{\partial\mathbf r}{\partial u}}{\left\|\frac{\partial\mathbf r}{\partial v}\times\frac{\partial\mathbf r}{\partial u}\right\|}$

The surface element reduces to

$\mathrm d\mathbf S=\mathbf n\,\mathrm dS=\mathbf n\left\|\dfrac{\partial\mathbf r}{\partial u}\times\dfrac{\partial\mathbf r}{\partial v}\right\|\,\mathrm du\,\mathrm dv$