Answer:
137
Step-by-step explanation:
This is an arithmetic sequence with first term (a₁) being 2 and common difference (d) being 11 - 2 = 9.
Explicit formula: aₙ = a₁ + (n - 1) * d so our formula is:
aₙ = 2 + (n - 1) * 9
= 2 + 9n - 9
= 9n - 7
a₁₆ = 9(16) - 7 = 137
Six books cost 17.94. Just multiply the amount of 1 book to the number of books there are.
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Define x :
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Let the smallest number be x.
The other two numbers will be x + 1 and x + 2.
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Construct Equation :
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Sum of these numbers is 72
⇒ x + x + 1 + x + 2 = 72
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Solve for x :
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x + x + 1 + x + 2 = 72
3x + 3 = 72
3x = 69
x = 23
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Find the numbers :
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1st number = x = 23
2nd number = x + 1 = 23 + 1 = 24
3rd number = x + 2 = 23 + 2 = 25
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Answer : The numbers are 23, 24 and 25.
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He can win 3 more tickets to get a prize.
30 tickets to win a prize - 27 tickets won already = 3 more tickets needed to win a prize.