Find all pairs of consecutive odd positive integers both of which are smaller than 10 such that their sum is more than 11
Let x be the smaller of the two consecutive odd positive integers. Then, the other integer is x + 2. Since both the integers are smaller than 10, x + 2 < 10 ⇒ x < 10 – 2 ⇒ x < 8 … (i) Also, the sum of the two integers is more than 11. ∴x + (x + 2) > 11 ⇒ 2x + 2 > 11 ⇒ 2x > 11 – 2 ⇒ 2x > 9
x>4.5 ------ Now wat to do
4.5<x<8
Then..hw to find the pairs!!
Let x be the smaller of the two consecutive odd positive integers. Then, the other integer is x + 2. Since both the integers are smaller than 10, x + 2 < 10 ⇒ x < 10 – 2 ⇒ x < 8 … (i) Also, the sum of the two integers is more than 11. ∴x + (x + 2) > 11 ⇒ 2x + 2 > 11 ⇒ 2x > 11 – 2 ⇒ 2x > 9
find the integers in this interval in such a way that if one is a then other is a + 2
(5,7) , (6,8).......
gud
is that correct!
yes
so...... wat abt (7,9)
but in my book there are only two answer (5,7) (7,9)............
because 6 and 8 are not odd
No need for x and y here. Just enumerate 1,3 3,5 5,7 7,9 Only the last two meet the second condition.
Gud @telliott99 but it seems that this question is based on inequality
@Yahoo! Ur book is correct
See, u get x can be 5,6,7 because it lies between 4.5 and 8 thus, x+2 can be 7,8,9 Now, 6 and 8 are even Thus only answer is (5,7) , (7,9)
aha..........thxx
is mine is correct
Yes, @best.shakir but u did what he had already done...... :)
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