Answer
it could be 73/x
Step-by-step explanation:
We will use demonstration of recurrences<span>1) for n=1, 10= 5*1(1+1)=5*2=10, it is just
2) assume that the equation </span>10 + 30 + 60 + ... + 10n = 5n(n + 1) is true, <span>for all positive integers n>=1
</span>3) let's show that the equation<span> is also true for n+1, n>=1
</span><span>10 + 30 + 60 + ... + 10(n+1) = 5(n+1)(n + 2)
</span>let be N=n+1, N is integer because of n+1, so we have
<span>10 + 30 + 60 + ... + 10N = 5N(N+1), it is true according 2)
</span>so the equation<span> is also true for n+1,
</span>finally, 10 + 30 + 60 + ... + 10n = 5n(n + 1) is always true for all positive integers n.
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Answer:
Kendra needs 3 coins (1 coin of 25 cent & 2 coins of 1 cent) to add 27 cents in 73 cents to make 1 dollar
Step-by-step explanation:
Given :
Kendra has 73 cents
She need 1 dollar to by a ball
∴ She requires additional money = 
Standard Coins available are 50 cents , 25 cents, 10 cents, 5 cents and 1 cent.
To make 27 cents = 
= 1 coin of 25 cent & 2 coins of 1 cent
Answer:
x = -30
Step-by-step explanation:
subtract 7 from both sides ( 7+2/5x -7, -5-7 )
simplify ( 2/5x = 12 )
multiply both sides by 5 ( 2/5x times 5 = 5 (-12) )
simplify ( 2x = -60 )
divide both sides by 2 ( 2x / 2, -60 / 2 )
x = -30
Answer:
The probability of drawing three red marbles is 1/27, or about 3.71%
Step-by-step explanation:
Add all the marbles:
5 + 4 + 6 = 15
Find favourable outcomes:
5
The probability for drawing a red marble is:
5/15 or 1/3
Multiply this ×3 to find the probability of drawing three red marbles.
1/3 × 1/3 × 1/3 = 1/27
1 ÷ 27 = 0.0370370370 ... repeating
