IBDP Mathematics Question Analysis Topic: Mathematics - Short Questions
Exam Questions:
1) The probability of getting an even number, when a die is thrown once, is..?
2) How many three-digit natural numbers are divisible by 7?
Answers:
For IBDP Mathematics, you should know:
1) A dice is thrown only once. As such, there are 6 total outcomes i.e., {1, 2, 3, 4, 5, 6}.
The favourable outcomes, aka the outcomes that an even number is rolled, is 3 i.e., {2, 4, 6}.
Therefore, the probability that an even number is rolled is 3/6 = 1/2.
2) First, we have to find out the first and last three digit numbers divisible by seven, which is 105 and 994 respectively.
Then, we can construct an arithmetic sequence where a = 105, d = 7 and tn = 994. (Let the number of terms be n.)
The nth term of tn = a + (n - 1)d
Therefore, 994 = 105 + (n - 1)7
994 - 105 = 7(n - 1)
n - 1 = 889 / 7
n = 128
As such, there are 128 three digit numbers divisible by 7.
Work hard for your IBDP Mathematics examination!
End of analysis. Great!