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3 years ago

The area of ABC is 72 square centimeters. find area of DEF

Mathematics

2 answers:

Sliva [168]3 years ago

8 0

20. because 100/5=20cm2

Rashid [163]3 years ago

5 0

Answer:

800

Step-by-step explanation:

Set up your proportion first (6/20 = 72/x). Then, square 6 and 20 (36/400 = 72/x). Cross multiply and divide (36x = 28800). Divide 28800 by 36 and that gives you 800 as your answer.

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Triangle ABC is similar to triangle FGH.

Ivan

Answer:

i can't understand the question but if you put a link I can figure it out

8 0

3 years ago

The sequence$$1,2,1,2,2,1,2,2,2,1,2,2,2,2,1,2,2,2,2,2,1,2,\dots$$consists of $1$'s separated by blocks of $2$'s with $n$ $2$'s i

kicyunya [14]

Consider the lengths of consecutive 1-2 blocks.

block 1 - 1, 2 - length 2

block 2 - 1, 2, 2 - length 3

block 3 - 1, 2, 2, 2 - length 4

block 4 - 1, 2, 2, 2, 2 - length 5

and so on.

Recall the formula for the sum of consecutive positive integers,

$\displaystyle \sum_{i=1}^j i = 1 + 2 + 3 + \cdots + j = \frac{j(j+1)}2 \implies \sum_{i=2}^j = \frac{j(j+1) - 2}2$

Now,

$1234 = \dfrac{j(j+1)-2}2 \implies 2470 = j(j+1) \implies j\approx49.2016$

which means that the 1234th term in the sequence occurs somewhere about 1/5 of the way through the 49th 1-2 block.

In the first 48 blocks, the sequence contains 48 copies of 1 and 1 + 2 + 3 + ... + 47 copies of 2, hence they make up a total of

$\displaystyle \sum_{i=1}^48 1 + \sum_{i=1}^{48} i = 48+\frac{48(48+1)}2 = 1224$

numbers, and their sum is

$\displaystyle \sum_{i=1}^{48} 1 + \sum_{i=1}^{48} 2i = 48 + 48(48+1) = 48\times50 = 2400$

This leaves us with the contribution of the first 10 terms in the 49th block, which consist of one 1 and nine 2s with a sum of $1+9\times2=19$ .

So, the sum of the first 1234 terms in the sequence is 2419.

8 0

2 years ago

Which expression shows 2 more than 1/5 times the sum of 7/12 and 3?

xenn [34]

The answer is D. 2+1/5×(7/12+3)

5 0

3 years ago

Jen uses 8.6 gallons of gasoline to drive 164.7 miles. Which is the best estimate for thenumber of miles per gallon of gasoline

zimovet [89]

Answer:

Step-by-step explanation:

164.7/8.6 = 19.15

about 20 miles per gallon

4 0

4 years ago

May anyone help please

lapo4ka [179]

Depending on how flexibly you interpret "about 20 times larger" to mean, the answers are B and D.

Check the ratios of the larger number to the smaller number:

A: (2.01 x 10^7)/(4.25 x 10^6) = 2.01/4.25 x 10^1 = 20.1/4.25 = 4.729

B: (8.21 x 10^-3)/(4.13 x 10^-4) = 8.21/4.13 x 10^1 = 82.1/4.13 = 19.879

C: (4.91 x 10^6)/(5.09 x 10^3) = 4.91/5.09 x 10^3 = 4910/5.09 = 964.637

D: (5.97 x 10^4)/(3.12 x 10^3) = 5.97/3.12 x 10^1 = 59.7/3.12 = 19.135

4 0

3 years ago