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3 years ago

Suppose y varies directly with x. Write an equation if y=75when x=25

Mathematics

1 answer:

ser-zykov [4K]3 years ago

6 0

Answer:

y = 3x

Step-by-step explanation:

The standard format of a directly proportional equation goes by the format of y = k × x. The question asks us to write an equation if y = 75 when x = 25 and y varies directly with x.

So we substitute the values y = 75 and x = 25 in the equation y = k × x

K = constant, we have to work this out

75 = k × 25

75 ÷ 25 = k

k = 75 ÷ 25

k = 3

k = 3 So then we put this back into the original y = k × x to find our final equation which is y = 3x

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sp2606 [1]

Answer:

Step-by-step explanation:

The TV to have a 16:9 ratio and have a diagonal of 65 inches must have a length & width whose squares add to 4,225 (65 squared) and whose ratio length and width simplifies to 16/9.

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D fails for the same reason as C.

Therefore A is the solution because $\frac{56.65}{31.86}=\frac{16}{9}$ and $65.65^2+31.86^2 = 65^2$

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3 years ago

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bija089 [108]

Answer: $\bold{a)\ P(t)=P_o\cdot e^{t\cdot ln(2.7)}}$

b) 5314

c) ln 2.7

d) 4.6 hrs

<u>Step-by-step explanation:</u>

$P(t) = P_o\cdot e^{kt}\\\\\bullet \text{P(t) is the number of bacteria after t hours} \\\bullet P_o\text{ is the initial number of bacteria}\\\bullet \text{k is the rate of growth}\\\bullet \text{t is the time (in hours)}\\\\\\270=100\cdot e^{k(1)}\\2.7=e^k\\ln\ 2.7=\ln e^k\\\boxed{ln\ 2.7=k}\\\\\text{So the equation to find the number of bacteria is: }\boxed{P(t)=P_o\cdot e^{t\cdot ln(2.7)}}\\\\\\P(4)=100\cdot e^{4\cdot ln(2.7)}\\.\qquad =\boxed{5314}$

$10,000=100\cdot e^{t\cdot ln(2.7)}\\100=e^{t\cdot ln(2.7)}\\ln\ 100=ln\ e^{t\cdot ln(2.7)}\\ln\ 100=t\cdot ln(2.7)\\\dfrac{ln\ 100}{ln\ 2.7}=t\\\\\boxed{4.6=t}$

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3 years ago

Suppose Amanda wants to have $800,000 in her IRA at the end of 30 years. She chooses to invest in an annuity that pays

VARVARA [1.3K]

Her IRA interest at the end of 30 years is mathematically given as

Interest= 438,765.56

<h3> IRA interest </h3>

Question Parameters:

N = 30
PV = 0
rate = 5%
FV = 800,000

Generally the equation for the payment function on excel is mathematically given as

A=PMT(rate, nper, pv, [fv], [type])

Therefore, inputting our functions

A=PMT(rate, nper, pv, [fv], [type])

where

A=PMT(5%, 30, 0, [800000], [])

A = 12,041.1481

Hence

interest = 800,000 - 30*12,041.1481

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For more information on Growth rate

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3 years ago

The Snow Sports Club from Sierra High School is boarding the tram at Heavenly Valley to ride up to the top of the mountain. The

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3 years ago

Read 2 more answers

Find the surface area.<br><br> Any help will be appreciated thank you

kozerog [31]

Answer:

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3 years ago