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3 years ago

Prove that the gregorian calendar repeats itself every 400 years.

1 answer:

3 0

The calendar obviously has an integral number of years and months in 400 years. If it has an integral number of weeks, then it will repeat itself after that time. The rules of the calendar eliminate a leap year in 3 out of the four century years, so there are 97 leap years in 400 years. The number of excess days of the week in 400 years can be found by ...

(303·365) mod 7 + (97·366) mod 7 = (2·1 + 6·2) mod 7 = 14 mod 7 = 0

Thus, there are also an integral number of weeks in 400 years.

The first day of the week is the same at the start of every 400-year interval, so the calendar repeats every 400 years.

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Plz help I need help

suter [353]

Answer:

7q + 12

Step-by-step explanation:

simply arrange the given expressions into the traditional way of adding numbers like 1 + 1 but vertically like : 1

1 +

which is equivalent to

6q + 1 +

q + 11

______

7q + 12

why? because 6q plus q is equal to 7q and 1 + 11 is equal to 12

good day.

4 0

2 years ago

At one point in 2011, there were approximately 2.1 billion internet users worldwide. If approximately 9/40 of the users lived in

Rufina [12.5K]

Estimating the number of internet users in Europe by multiplying the ratio with the whole internet users
users in Europe = 9/40 × 2.1 billion
users in Europe = 9/40 × 2,100 million
users in Europe = (9 × 2,100)/40 million
users in Europe = 18,900/40 million
users in Europe = 472.5 million

The number of internet users in Europe is approximately 472.5 million at this time

7 0

3 years ago

Solve 3x + k = c for x

olasank [31]

Here we are given the equation 3x+k =c

Here in order to solve for x , first let us bring k to the right side.

k is in addition on the left , so when we bring it to the right it gets subtracted

$3x=c-k$

now we have to isolate x on the left side , 3 is in multiplication with x , so when we bring it to the right side we divide by 3

Answer: $x=\frac{(c-k)}{3}$

7 0

3 years ago

Read 2 more answers

Every day, a comes to the bus stop at the same time, and boards the first bus that arrives. the arrival of the first bus is an e

mylen [45]

So the waiting time for a bus has density f(t)=λe−λtf(t)=λe−λt, where λλ is the rate. To understand the rate, you know that f(t)dtf(t)dt is a probability, so λλ has units of 1/[t]1/[t]. Thus if your bus arrives rr times per hour, the rate would be λ=rλ=r. Since the expectation of an exponential distribution is 1/λ1/λ, the higher your rate, the quicker you'll see a bus, which makes sense.

So define X=min(B1,B2)X=min(B1,B2), where B1B1 is exponential with rate 33 and B2B2 has rate 44. It's easy to show the minimum of two independent exponentials is another exponential with rate λ1+λ2λ1+λ2. So you want:

P(X>20 minutes)=P(X>1/3)=1−F(1/3),P(X>20 minutes)=P(X>1/3)=1−F(1/3),

where F(t)=1−e−t(λ1+λ2)F(t)=1−e−t(λ1+λ2).

8 0

2 years ago

Please help me with this thanks so much to whoever is helping me

netineya [11]

Answer:

X = 80

Step-by-step explanation:

A flat line is equal to 180 degrees, meaning that if you use linear, you can find out that if you subtract 100 from it, it becomes 80, which resembles the X.

8 0

1 year ago