Answer:
40
Step-by-step explanation:
Use the Outside Angles Theorem,

2.86 the negatives will cancel it self den u divide it
Step 1. Set up long division
_______
7| 1 9 8 6
Step 2. <span>Calculate 19 ÷ 7, which is 2 with a remainder of 5.
2
</span> _______
7| 1 9 8 6
1 4
_________
5
Step 3. Bring down 8, so that 58 is large enough to be divided by 7.
2
_______
7| 1 9 8 6
1 4
_________
5 8
Step 4. <span>Calculate 58 ÷ 7, which is 8 with a remainder of 2.
</span> 2 8
_______
7| 1 9 8 6
1 4
_________
5 8
5 6
_________
2
Step 5. <span>Bring down 6, so that 26 is large enough to be divided by 7.
</span> 2 8
_______
7| 1 9 8 6
1 4
_________
5 8
5 6
_______
2 6
Step 6. Calculate 26 ÷ 7, which is 3 with a remainder of 5.
2 8 3
_______
7| 1 9 8 6
1 4
_________
5 8
5 6
_______
2 6
2 1
______
5
Step 7. <span>Therefore, 1986 ÷ 7 = 283 with a remainder of 5.
823 With a remainder of 5
Done!
</span><span>Decimal Form If Needed: 283.714286</span>
Answer:
Step-by-step explanation:
This is a Combination (as in permutation vs combination) question the symbol (n r) refers to "n choose r". This is sometimes written as nCr
i.e the question is asking you to find how many combinations each will yield when you chose r items from n item without repetition and order does not matter.
I will only do the first question for you and you can just follow the same steps to solve the rest of the questions.
Recall that

Consider question a) we are given (5 1) or ₅C₁
we can see that n = 5 and r = 1
If we substitute this into the formula:
₅C₁ = (5!) / [ (1!)(5- 1)!]
= (5!) / [ (5- 1)!]
= (5!) / (4!)
= (5·4·3·2·1) / (4·3·2·1)
= 5
hence ₅C₁ = 5