Answer:
8
Step-by-step explanation:
average is calculated as
average = 
= 13 ( multiply both sides by 2 )
sum of 2 eldest = 26
Then for the 4 children
average = 
= 
= 8
Answer:
Step-by-step explanation:
The equation for that is
If we subtract over the 70, we have a quadratic that we can factor to solve for the values of x that will make that equation true.
Now we need the factors of 70 that will either add or subtract to give us the linear term of 3. The factors of 70 that will work are 10 and 7. 10 times 7 is 70, and 10 - 7 = 3:
and now we will factor by grouping:
and factor out what's common:
The factor (x + 10) is common, so we will now factor that out:
By the Zero Product Property, either x + 10 = 0 or x - 7 = 0, so x = -10 or 7
Those are the 2 numbers that will work.
simplifies to
100 - 30 which does in fact equal 70. OR
which simplifies to
49 + 21 which also equals 70.
So you're done!
Answer:
D
Step-by-step explanation:
none of the option satisfy the equation
Answer:
6.4 meters per second
Step-by-step explanation:
Sarah the cheetah ran 100 meters at a speed of 16.8 meters per second. An olympian ran the 100-meter dash in 9.6 seconds. How much faster was Sarah the cheetah’s speed, to the nearest tenth of a meter per second?
0.9 meters per second
1.6 meters per second
6.4 meters per second
10.4 meters per second
Speed = distance / time
Olympian's speed = 100 / 9.6 = 10.4 meters per second
Sarah's speed = 16.8 meters per second.
Difference in speed = 16.8 - 10.4 = 6.4
the tenth is the first number after the decimal place. To convert to the nearest tenth, look at the number after the tenth (the hundredth). If the number is greater or equal to 5, add 1 to the tenth figure. If this is not the case, add zero
Answer:
C
Step-by-step explanation:
Noting that
+ (- ) is equivalent to subtraction
- (- ) is equivalent to addition
Given
13 + (- 12) - (- 5)
= 13 - 12 + 5
= 1 + 5
= 6 → C
