Answer:
Cooler - 9.8 hours | Dami - 39.2 hours
Step-by-step explanation:
If Dami works 4 times as much as Cooler, and Cooler works x hours every week, then Dami works 4*x hours every week, or 4x. Since the combined time they work is 49 hours, we can represent this in the equation 4x+x=49, or 5x=49. Dividing both sides by 5 we get x=9.8.
Since Cooler works x hours every week, he worked for 9.8 hours. And since Dami works 4x hours every week, she worked 4*9.8 hours=39.2 hours.
Formula because that is the answer
Answer:
a=21
AB=23.9
BC=19.5
CD=(23.9)
AD=19.5
Step-by-step explanation:
Each pair of parallel sides are equal in a parallelogram. Sense both pairs use the same variable we can just choose the easiest to solve which would be:
a-1.5=19.5
add 1.5 to both sides
a=21
now substitute 21 in for a in each equation.
AB=CD so
AB=23.9
BC=AD so
BC=19.5
CD=(21)+2.9 so
CD=(23.9)
AD is given so
AD=19.5
.4 is tenths .42 is hundredths and .422 is thousandths
Answer:
If there is 1 at the top, then you have 1, then 2, then 3, etc.
total number of oranges equals:
1 + 2 + 3 + ... + 16 + 17 + 18 <-- stop at 18 because this is the number of oranges at the base
You can use the formula:
sum of first n numbers = n*(n + 1)/2
-->
18*19/2 = 9*19 = 171
or you can figure it out (basically derive the above formula):
you have:
1 + 18 = 19
2 + 17 = 19
3 + 16 = 19
...
How many pairs do you have? Well, it's just the number of numbers: 1-18 = 18 numbers (divide by 2) = 9 pairs)
9 pairs of 19 = 9 * 19 = 171
Hope this helps!
Step-by-step explanation: