Hello from MrBillDoesMath!
Answer:
8
Discussion:
Let the number be "n". Then the question states that
3n - 15 = (n/2) + 5 => multiply both sides by 2
6n - 30 = n + 10 => subtract n from both sides
5n - 30 = 10 => add 30 to both sides
5n = 30 + 10 = 40 => divide both sides by 5
n = 40/5 = 8
Thank you,
MrB
Answer:
Olga's mistake was in Step 3 because she divided the entire equation by 3 instead of dividing it by 1/3.
Answer:
I assume you know Arithmetic Progression .
so, we have to find the first and last 4-digit number divisible by 5
first = 1000 , last = 9990
we have a formula,
= a + (n-1)d
here,
is the last 4-digit number divisible by 5.
n is the number of 4-digit even numbers divisible by 5
d is the common difference between the numbers, which is 10 in this case
a is the first 4-digit number divisible by 5
9990 = 1000 + (n-1)*10
899 = n-1
n = 900
Hence, there are 900 4-digit even numbers divisible by 5
Answer:
The answer is the 2nd one
Step-by-step explanation:
10[(6 + 4) / 2]
10[10/2]
10 * 5
50 <==