All categories

3 years ago

Please help me I will offer 20 points

Mathematics

1 answer:

sveticcg [70]3 years ago

5 0

Answer:

9.3 x 8.5 = 79.05

7.6 x 2.4 = 18.24

an easier way to multiply decimals is to take away decimals and add later

example: 9.<u>3</u>x8.<u>5</u> > 93x85 = 7905 since there are two places behind the decimal add that many to the solution 7905 > 79.05

You might be interested in

At a fast food restaurant, 10 cheeseburgers w/onion and 5 orders of french fries contain 6900 calories. 5 cheeseburgers w/oni

Leona [35]

Write the equations,

10 c + 5 f = 6900

5c + 3f = 3660

Double,

10c + 6f = 7320

Subtract,

f = 7320 - 6900 = 420

10 c = 6900 - 5f = 6900 - 2100 = 4800

c = 480

Answer: Cheeseburger 480 calories, fries 420 calories

Check:

10 (480) + 5 (420) = 4800 + 2100 = 6900 good

5(480) + 3(420) = 2400 + 1260 = 3660 good

5 0

2 years ago

Petri did the following problem but got the wrong answer. She needs to correct her mistake and turn the problem back in.

zubka84 [21]

Answer:

she needs to subtract 5-3 first

Step-by-step explanation:

4 0

2 years ago

The rate of change of the number of squirrels S(t) that live on the Lehman College campus is directly proportional to 30 − S(t),

pishuonlain [190]

Answer:

S(3)=22

Step-by-step explanation:

The rate of change of the number of squirrels S(t) that live on the Lehman College campus is directly proportional to 30 − S(t).

$\dfrac{dS}{dt}=k(30-S(t))\\ \dfrac{dS}{dt}+kS(t)=30k\\$The integrating factor: e^{\int k dt}=e^{kt}\\$Multiply all through by the integrating factor\\ \dfrac{dS}{dt}e^{kt}+kS(t)e^{kt}=30ke^{kt}$

$(Se^{kt})'=30ke^{kt} dt\\$Integrate both sides\\ Se^{kt}=\dfrac{30ke^{kt}}{k}+C$ (C a constant of integration)\\Se^{kt}=30e^{kt}+C\\$Divide both sides by e^{kt}\\S(t)=30+Ce^{-kt}$

When t=0, S(t)=15

$15=30+Ce^{-k*0}\\C=15-30\\C=-15$

When t = 2, S(t)=20

$20=30-15e^{-2k}\\20-30=-15e^{-2k}\\-10=-15e^{-2k}\\e^{-2k}=\dfrac23\\$Take the natural log of both sides$\\-2k=\ln \dfrac23\\k=-\dfrac{\ln(2/3)}{2}$

Therefore:

$S(t)=30-15e^{\frac{\ln(2/3)}{2}t}\\$When t=3$\\S(t)=30-15e^{\frac{\ln(2/3)}{2} \times 3}\\S(3)=21.8 \approx 22$

8 0

2 years ago

HELP PLEASE 20 POINTS TO GET IT RIGHT

Contact [7]

Answer:

hope this helps!!:)

Step-by-step explanation:

8 0

2 years ago

The length of bills backyard swimming pool is 60 feet longer than the width of the pool. The surface area of the water is 1600 s

shutvik [7]

Answer:

The width is 20 ft and the length is 80 ft

Step-by-step explanation:

Area = l * w

l = w +60

SA = 1600 ft^2 ( which is the regular area) The surface area of the water is just what is on top which is length times width

1600 = l*w

Substitute in l = w+60

1600 = (w+60) *w

Distribute the w

1600 = w^2 +60w

Subtract 1600 from each side

1600-1600 = w^2 + 60w -1600

0 = w^2 + 60w -1600

Factor

0=(w-20) (w+80)

Using the zero product property

w-20=0 w+80 =0

w=20 or w=-80

The width cannot be negative so

w=20

Now we need to find the length

l = w+60

l = 60+20

l =80

7 0

2 years ago