1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
attashe74 [19]
2 years ago
5

Jordan is starting to save $150 to buy a new cell phone. In December, he saved $5. In January, he plans twice as much as he did

in December, for a total savings of $15 ($5 + $10). If Jordan continues to save twice as much he saved from the previous month, in which month will his total savings will be enough to buy the phone.
Mathematics
1 answer:
Goryan [66]2 years ago
5 0

9514 1404 393

Answer:

  April

Step-by-step explanation:

The sequence of amounts saved is a geometric sequence. The sum of those amounts is given by the formula ...

  Sn = a1·(r^n -1)/(r -1)

where a1 is the amount saved in month 1, r is the common ratio, and n is the number of months. We want to find n such that ...

  150 ≤ 5(2^n -1)/(2 -1)

  30 ≤ 2^n -1

  31 ≤ 2^n

We can solve this using logarithms, or we can make use of our knowledge of powers of 2: 2^5 = 32. That is, n = 5 will be the first month when Jordan's total savings exceeds $150.

The fifth month will be April. Jordan's total savings will be enough in April.

__

The attached shows a spreadsheet that computes Jordan's amount of savings each month, and his running total. Once the formulas are written, they can be copied down as far as required to see where the total savings is enough.

You might be interested in
$10.50 for 3 pounds round to the nearest hundredth can u solve the other pens too .
Nookie1986 [14]

Answer: 3: $3.50 for one pound

4: The value of X is 10

5: P has the value of 2

Step-by-step explanation:

4 0
3 years ago
I promise I will mark as brainiest if a speed of a car increase its average speed in a journey of 200 miles by 5 mile/hour the j
jok3333 [9.3K]

Answer:

\large \boxed{\sf \ \ \ \dfrac{\sqrt{4025}-5}{2}=29.22144... \ \ \ }

Step-by-step explanation:

Hello

<u>Let's note the original speed of the car v</u>

it means that in 1 hour he is going v miles

so to go 200 miles it takes ( in hour)

\dfrac{200}{v}

If the speed of the car is v+5 than to go 200 miles it takes (in hour)

\dfrac{200}{v+5}

and this time is one hour less so we can write

\boxed{\sf \ \ \dfrac{200}{v+5}=\dfrac{200}{v}-1 \ \ }

We can multiply by v(v+5) both parts of the equation so

200v=200(v+5)-v(v+5)\\\\200v=200v+1000-v^2-5v\\\\v^2+5v-1000=0

\Delta=b^2-4ac=5^2+4*1000=4025\\\\ \text{There are potential solutions }\\\\\ \ \ \ \ x_1=\dfrac{-5-\sqrt{4025}}{2}\\\\\ \ \ \ \ x_2=\dfrac{-5+\sqrt{4025}}{2}

Only one is positive and this is is

x_1=\dfrac{\sqrt{4025}-5}{2}=29.22144...

So the original speed is 29.22144... mph

Hope this helps.

Do not hesitate if you need further explanation.

Thank you

7 0
3 years ago
The price of a burger meal changed from $5.00 to $7.50. What is the percent change in the cost of the burger meal ?
Gala2k [10]

Answer:

50%

Step-by-step explanation:

(V2−V1)|V1|×100

=(7.5−5)|5|×100

=2.55×100

=0.5×100

=50%change

=50%increase

4 0
3 years ago
Suppose a projectile is fired from a cannon with velocity v0 and angle of elevation θ. The horizontal distance Rθ it travels (in
jolli1 [7]

Answer:

0.25 rad to the nearest hundredth radian

Step-by-step explanation:

Here is the complete question

Suppose a projectile is fired from a cannon with velocity vo and angle of elevation (theta). The horizontal distance R(θ) it travels (in feet) is given by the following.  

R(θ) = v₀²sin2θ/32

If vo=80ft/s what angel (theta) (in radians) should be used to hit a target on the ground 95 feet in front of the cannon?

Do not round any intermediate computations, and round your answer(s) to the nearest hundredth of a radian.

(θ)= ?rad

Solution

R(θ) = v₀²sin2θ/32

If v₀ = 80 ft/s and R(θ) = 95 ft

θ = [sin⁻¹(32R(θ)/v₀²)]/2

= [sin⁻¹(32 × 95/80²)]/2

=  [sin⁻¹(3040/6400)]/2

=  [sin⁻¹(0.475)]/2

= 28.36°/2

= 14.18°

Converting 14.18° to radians, we have 14.18° × π/180° = 0.2475 rad

= 0.25 rad to the nearest hundredth radian

3 0
2 years ago
Find the total surface area of these solids
12345 [234]
<h2>Step-by-step explanation:</h2><h3>We firstly find the surface area of only one face of the cube:</h3><h3>Sa=a²</h3><h3>Sa=1.2²cm</h3><h3>Sa=1.44cm²</h3>

<h2>Since the cube has 6 faces we multiply the surface area of one face(144cm²) with 6</h2>

Area(cube)=1.44cm²*6

=8.64cm²

<h2>Same thing with the prism but we have to find the area of one of his triangle face and rectangle face</h2>

S(triangle)=5mm*4mm*1/2

=10mm²

S(rectangle)=7mm*5mm=35mm²

<h2>The prism has 2 triangle faces and three rectangle faces so we multiply the area by those numbers and then we add those together to get the final area</h2>

S=10mm²*2+35mm²*3

S=20+105

S=125mm²

<h3><em>Hope this helped..</em></h3><h3 /><h3><em>Hope this helped..Brainliest pls..</em></h3>
4 0
2 years ago
Other questions:
  • What is the mode of the following numbers? 8,10,8,5,4,7,5,10,8
    13·1 answer
  • 85000 nearest to 10,100,1000,10000
    15·1 answer
  • Need help timed !!! Math question!!^( '-' )^
    15·2 answers
  • The area of a square mirror is 256 in². A rectangular mirror has a width the same as the square mirrors width. Its length is two
    9·2 answers
  • What’s the output of f(x)=3-4x
    8·1 answer
  • Help me pls I’m new to this pls answer if you know it thank you!
    6·1 answer
  • The quotient of (x5 – 3x3 – 3x2 – 10x + 15) and a polynomial is (x2 – 5). What is the polynomial?
    9·1 answer
  • A recipe calls for 3 cups of sugar for
    8·1 answer
  • Help! Plz!
    14·2 answers
  • Press the hotspots of the relationships shown that are linear functions.
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!