All categories

2 years ago

1 − 2 + 3 −... + 99 Please solve!

Mathematics

1 answer:

Lemur [1.5K]2 years ago

6 0

Answer:

Step-by-step explanation:

So you can think of this by grouping it like this:

(1-2) + (3-4) + (5-6) + ... + (97-98) + 99

which is equal to: (-1) + (-1) + (-1)... + (-1) + 99

(each group is equal to -1, and 99 won't have a pair since it's the last one)

then, find how many groups of -1 there are:

the groups start at 1 and end at 98, but there are two in each group, so 98/2 = 49. this means there are 49 groups.

so now, you know that there are 49 -1s, so 49 * (-1) = -49.

finally, you can't forget the extra 99 that didn't have a pair, so -49 + 99 = 50.

You might be interested in

PLEASE ANSWER IN THE SCREENSHOT. I WILL MARK BRAINLYEST

Nimfa-mama [501]

Yes, the table is correct
There would be 60 squares as the ratio of triangles to squares is 3:4

6 0

3 years ago

Answer below please!

poizon [28]

Answer:

$x=-\frac{11}{18}$

Step-by-step explanation:

$-1\frac{7}{9}=(-2\frac{5}{6} + \frac{1}{3})x$

Solve parenthesis first

$-2\frac{5}{6} + 1/3$

Find a common denominator.

The common denominator would be 6.

Because the first expression already has a denominator of 6 it stays the same.

$\frac{1}{3} = \frac{2}{6}$

$-2\frac{5}{6} + \frac{2}{6} = -2\frac{7}{6} = -1\frac{1}{6}$

Put that into the original equation.

$-1\frac{7}{9}=(-1\frac{1}{6} )x$

Isolate the x. Add $1\frac{1}{6}$ to each side.

$-1\frac{7}{9}+ 1\frac{1}{6}=x$

Find a common denominator.

we can use 18 as the common denominator.

$-1\frac{7}{9}+ 1\frac{1}{6}= -1 \frac{14}{18} +1\frac{3}{18}= x$

Add.

$-\frac{11}{18} =x$

We cannot simplify so our answer stays the same.

6 0

2 years ago

In Cecilia’s CD collection, 1/5 of her Jazz CDs represents 1/10 of all her CDs. What is the ratio of her Jazz CDs to her non-Jaz

KatRina [158]

Answer: The required ratio is 1:1.

Step-by-step explanation:

Let the total number of CDs be 100

$\frac{1}{10}$ of CDs is given by

$\frac{1}{10}\times 100\\\\=10$

According to question,

$\frac{1}{5}$ of her Jazz CDs represents $\frac{1}{10}$ of all her CDs.

Let the number of Jazz CDs be x

So, it becomes

$\frac{1}{5}\times x=10\\\\x=10\times 5\\\\x=50$

So, Number of Jazz's CDs is 50

Number of Jazz non CDs is given by

$100-50=50$

Ratio of her CDs to her non- CDs is given by

$50:50\\\\1:1$

Hence, the required ratio is 1:1.

6 0

3 years ago

19/5 as a mixed number

Feliz [49]

The answer would be 3 and 4 over 5

8 0

4 years ago

Read 2 more answers

Square root of 81 minus square root of negative 48 answer in a + bi form

galina1969 [7]

Answer:

9-6.92820323i Nothing else can be done.

Step-by-step explanation:

-48 is not a perfect square but 81 is a square. When you try to square -48 it comes to be 6.92820323i.

4 0

4 years ago