Answer:
51
1−2+3−4+5−.....+101
=(1+3+5+.....+101)−(2+4+6+.....+100)
=(1+3+5+.....+101)−2(1+2+3+.....+50)
=(51)
2
−2(
2
50(50+1)
)
=2601−2×1275
=2601−2550
=51
Hope the shown work helps you!!
Answer:
7 Quarters and 3 dimes
Step-by-step explanation:
You have to find how many quarters (0.25) and dimes (0.10) are in $2.05. There are 7 quarters, which will add up to $1.75. You can't have 8 quarters because then you would have 2 dollars, and there wouldn't be enough for a dime, there would only by 5 cents left, or a nickle. Then, you find out how many nickels you need, which is 3.
.10x3=.30. 1.75+0.3=2.05.
I hope you understood:)
Answer:
I'm 21 looking at people who don't now how to do this
I'm pretty sure this is true