Wesley and Delia are playing a math game. Wesley gives Delia these step to follow.
Step 1: Multiply a number by 6 and then subtract by 4.
Step 2: Divide the result by 2
Step 3: Add 3 to the result from the second step.
If Delia's final answer is 19, What was the original number?
PLEASE HELP ME!!!
suppose you pick x
1: 6x - 4
2: (6x-4)/2 = 3x-2
then 3x-2 = 19
3x = 21
x = 7
Delia picked 7
or you can just do everything with inverse operations on reverse order
last thing she did was divide by 2
so first thing we do is multiply by 2
19x2 = 38
the middle thing she did was subtract 4, so we will add 4
38+4 =42
the first thing she did was to multiply be 6, so the last thing we will do is divide by 6
42÷6 = 7
How about that ???
i guess it will help.. thank you :)
To find the original number, let's work backward through the steps given.
Step 3 tells us to add 3 to the result from step 2.
So, if Delia's final answer is 19, we need to subtract 3 from that to get the result from step 2.
19 - 3 = 16
Step 2 tells us to divide the result by 2.
So, to find the original number, we need to multiply the result from step 2 by 2.
16 x 2 = 32
Now we have the number before step 2.
Step 1 tells us to multiply a number by 6 and then subtract 4.
So, to find the original number, we need to add 4 to the result from step 1 and then divide by 6.
Let's call the original number "x".
Step 1: 6x - 4
Step 2: (6x - 4)/2 = 32
To find "x", we need to undo the operations in step 1. First, we multiply by 2, then add 4, and finally divide by 6.
(32 x 2 + 4)/6 = (64 + 4)/6 = 68/6 = 11.33...
Therefore, the original number "x" is approximately 11.33.