Answer:
5.25 feet
Step-by-step explanation:
Just press this into your calculator
Answer:
The river is 3.15 feet deep.
Step-by-step explanation:
First let's recognize what we need to find: the depth of the river
We know last year the river was 4.2 feet deep, but it dropped 25%. This means we also need to find how much it dropped. To find this, we need to know what 25% of 4.2 is. Write an equation for this.
y = 25% of 4.2
y = 0.25 • 4.2
y = 1.05
This means that the river dropped 1.05 feet. To know its depth now, we need to subtract 1.05 from 4.2. Write an equation for this.
d = 4.2 - 1.05
d = 3.15
The river is 3.15 feet deep.
Hope this helps!
Answer:

Step-by-step explanation:
The error in rounding a number is half of the unit of measure.
The number was rounded to the nearest 0.1 unit so the error is 1/2×0.1, which equals 0.05.
Now we add 3.7 and 0.05, which equals 3.75 and we also take 3.7 - 0.05, which equals 3.65
So, the error interval is:

Well in this problem we just have to work backwards doing everything opposite of what she did in order to get the final answer.
so she has 39 stamps at this moment. and since she bought nine more stamps lets subtract that value to see what she had before that.
1.) 39 - 9 = 30
now she has 30. but she said that before step one she sold half of them to buy that video game. so she divided her starting number by two. so again we are going to work backwards by multiplying the number by 2:)
2.) 30 x 2 = 60!!
3.) So she started out with 60 stamps
answer is 60:)
hope i helped