I keep getting this wrong and I only have one chance to get it right. Please help! It's timed aswell.

A country will produce 3000 missiles this year. Each of the short-range missiles cost $200000 to produce. Each of the medium-ran

Lynna [10]

Answer:

$350,000

Step-by-step explanation:

Let's define:

s: amount of short-range missiles produced

m: amount of medium-range missiles produced

l: amount of long-range missiles produced

From the total production and the ratios we can write the following equations:

s + m + l = 3000

s/m = 3/3 = 1 = m/s

s/l = 3/4 or l/s = 4/3

Dividing the first equation by s, we get:

s/s + m/s + l/s = 3000/s

1 + 1 + 4/3 = 3000/s

10/3 = 3000/s

s = 3000*3/10 = 900

m = 900

l = 4/3*900 = 1200

From the money that the countries plans to use and each missile cost, we can write the following equation:

200,000*s + 300,000*m + cost*l = 870,000,000

Replacing with previous result:

200,000*900 + 300,000*900 + cost*1200 = 870,000,000

cost = (870,000,000 - 200,000*900 - 300,000*900)/1200 = 350,000

3 0

3 years ago

While Patrick was visiting his sister in Summerfield, he bought a silver ring that was marked down 50% from an original price of

Bezzdna [24]

21.47 I think???? Not sure

7 0

3 years ago

What is y=-10x's constant of proportionality and how would describe a graph's constant rate of change.

Fantom [35]

Okay, so here, we know that -10 is the slope, therefore, it is also the constant of proportionality.

'x' is the unknown value, that tells us to multiply by -10.

So, on a graph, we would consider that per unit, it would decrease by -10, since its a negative slope.

Hope I helped, if you have further questions or concerns, feel free to PM me. Thanks! :D

5 0

3 years ago

find the area of the trapezium whose parallel sides are 25 cm and 13 cm The Other sides of a Trapezium are 15 cm and 15 CM

Snezhnost [94]

$\huge\underline{\red{A}\blue{n}\pink{s}\purple{w}\orange{e}\green{r} -}$

Given - A trapezium ABCD with non parallel sides of measure 15 cm each ! along , the parallel sides are of measure 13 cm and 25 cm

To find - Area of trapezium

Refer the figure attached ~

In the given figure ,

AB = 25 cm

BC = AD = 15 cm

CD = 13 cm

Construction -

$draw \: CE \: \parallel \: AD \: \\ and \: CD \: \perp \: AE$

Now , we can clearly see that AECD is a parallelogram !

$\therefore$ AE = CD = 13 cm

Now ,

$AB = AE + BE \\\implies \: BE =AB - AE \\ \implies \: BE = 25 - 13 \\ \implies \: BE = 12 \: cm$

Now , In ∆ BCE ,

$semi \: perimeter \: (s) = \frac{15 + 15 + 12}{2} \\ \\ \implies \: s = \frac{42}{2} = 21 \: cm$

Now , by Heron's formula

$area \: of \: \triangle \: BCE = \sqrt{s(s - a)(s - b)(s - c)} \\ \implies \sqrt{21(21 - 15)(21 - 15)(21 - 12)} \\ \implies \: 21 \times 6 \times 6 \times 9 \\ \implies \: 12 \sqrt{21} \: cm {}^{2}$

Also ,

$area \: of \: \triangle \: = \frac{1}{2} \times base \times height \\ \\\implies 18 \sqrt{21} = \: \frac{1}{\cancel2} \times \cancel12 \times height \\ \\ \implies \: 18 \sqrt{21} = 6 \times height \\ \\ \implies \: height = \frac{\cancel{18} \sqrt{21} }{ \cancel 6} \\ \\ \implies \: height = 3 \sqrt{21} \: cm {}^{2}$

Since we've obtained the height now , we can easily find out the area of trapezium !

$Area \: of \: trapezium = \frac{1}{2} \times(sum \: of \:parallel \: sides) \times height \\ \\ \implies \: \frac{1}{2} \times (25 + 13) \times 3 \sqrt{21} \\ \\ \implies \: \frac{1}{\cancel2} \times \cancel{38 }\times 3 \sqrt{21} \\ \\ \implies \: 19 \times 3 \sqrt{21} \: cm {}^{2} \\ \\ \implies \: 57 \sqrt{21} \: cm {}^{2}$

hope helpful :D

6 0

2 years ago

Drisen has 6 groups of trains. Each group has 3 trains in it. What addition number sentence would help him solve how many trains

Nimfa-mama [501]

Answer:

6x3=x

x=18

Step-by-step explanation: plzz mark brainliest

4 0

3 years ago