I need help with a math question

Suppose you are asked to find the area of a rectangle that is 2.1-cm wide by 5.6-cm long. Your calculator answer would be 11.76

yKpoI14uk [10]

Answer:

12 cm²

Step-by-step explanation:

Length of rectangle = 5.6 cm

Width of rectangle = 2.1 cm

Area of rectangle = Length of rectangle×Width of rectangle

⇒Area of rectangle = 5.6×2.1

⇒Area of rectangle = 11.76 cm²

11.76 has 4 significant figures in order to write this term in 2 significant terms we round of the term

The last digit in the decimal place is 6. Now, 6≥5 so we round the next digit to 8 we get

11.8

Now the last digit in the decimal place is 8. Now, 8≥5 so we round the next digit to 2 we get

12

∴ Hence the area of the rectangle when rounded to 2 significant figures is 12 cm²

5 0

3 years ago

A radioactive substance decreases in the amount of grams by one-third each year. If the starting amount of the

katovenus [111]

Answer:

The sequence is geometric. The recursive formula is $a_{n}=2/3a_{n-1}$

Step-by-step explanation:

In order to solve this problem, you have to calculate the amount of the substance left after the end of each year to obtain a sequence and then you have to determine if the sequence is arithmetic or geometric.

The substance decreases by one-third each year, therefore:

After 1 year:

$1452-\frac{1}{3}(1452)$

Using 1452 as a common factor and solving the fraction:

$1452(1-\frac{1}{3})=1452(\frac{2}{3})=968$

You can notice that in general, after each year the amount of grams is the initial amount of the year multiplied by 2/3

After 2 years:

$968(\frac{2}{3})=\frac{1936}{3}$

After 3 years:

$\frac{1936}{3}(\frac{2}{3})=\frac{3872}{9}$

The sequence is:

1452,968,1936/3,3872/9....

In order to determine if the sequence is geometric, you have to calculate the ratio of two consecutive terms and see if the ratio is the same for all two consecutive terms. The ratio is obtained by dividing a term by the previous term.

The sequence is arithmetic if the difference of two consecutive terms is the same for all two consecutive terms.

-Calculating the ratio:

For the first and second terms:

968/1452=2/3

For the second and third terms:

1936/3 ÷ 968 = 2/3

In conclussion, the sequence is geometric because the ratio is common.

The recursive formula of a geometric sequence is given by:

$a_{n}=ra_{n-1}$

where an is the nth term, r is the common ratio and an-1 is the previous term.

In this case, r=2/3

7 0

3 years ago

Tug of War Activity

guapka [62]

Answer:

Round 3 the grandmas

Step-by-step explanation:

6 0

3 years ago

Which shows a set of figures that always possesses all these attributes?

Scilla [17]

Answer:

C

Step-by-step explanation:

Four right angles eliminates trapezoids.

Four right angles also eliminates any triangle

General quadrilaterals should be eliminated by the 4 right angles. If they have 4 right angles, the figure is not a general quadrilateral.

The answer is rectangles and squares.

5 0

3 years ago

The Canadian side of Niagara Falls has a flow rate of 600,000 gallons per second. How many gallons of water flow over the falls

Olenka [21]

Answer:

hope this helps 3,160 tons of water flows over Niagara Falls every second. This accounts for 75,750 gallons of water per second over the American and Bridal Veil Falls and 681,750 gallons per second over the Horseshoe Falls.

Step-by-step explanation:

brainlist would help thx

5 0

2 years ago