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2 years ago

79 x 31 rounding or compatible numbers . show how you estimate

Mathematics

1 answer:

Lubov Fominskaja [6]2 years ago

8 0

Answer:

80 × 30 = 2,400

Step-by-step explanation:

We can easily round 79 up to 80 and round 31 down to 30. This would make our expression 80 × 30, which is much easier to compute. We just take 8 × 3 (which is 24) and add two zeros onto the end of the number. This yields us an answer of 2,400 which is very close to the actual multiplication of 79 × 31 which is 2,449 (only 49 more than our estimation).

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Please help me on this

11111nata11111 [884]

Answer: 11 boxes of cards for $72

Step-by-step explanation:

Brennan's equation would be

y=6x+6

Gabriel's Equation would be

y=5x+17

when they spend the same amount the equations will be equal

6x+6=5x+17

x+6= 11

x=11

so 11 boxes they would spend the same

To figure out cost, put 11 into the first equations

y=6(11)+6= 66+6= 72

y=5(11)+17= 55+17 = 72

so they each spent $72

5 0

2 years ago

The simple interest formula is I=Prt , where I is the interest, P is the principal, r is the interest rate, and t is the time.

DaniilM [7]

t = 5.3 years
(about 5 years 4 months)

Equation:
t = (1/r)(A/P - 1)
Calculation:
First, converting R percent to r a decimal
r = R/100 = 7.2%/100 = 0.072 per year,
then, solving our equation

t = (1/0.072)((4835.6/3500) - 1) = 5.3
t = 5.3 years

6 0

2 years ago

Find the missing number sequence

tamaranim1 [39]

Answer:

its ment to be 83

Step-by-step explanation:

5 0

2 years ago

Suppose you estimated square root of 12 by averaging a square like rectngle.What would be a reasonable estimation?

sesenic [268]

Answer:

3.5.

Step-by-step explanation:

3^2 = 9

and 4^2 = 16 so the square root is between 3 and 4.

Take a rectangle 3.4 by 3.6:

the area = 3.4 * 3.6 = 12.24 so an estimate of the square root could be 3.5.

3.5 * 3.5 = 12.25.

5 0

2 years ago

A circle has a circumfernce of 13 it has a arc length of 11. What is the central angle of the arc in degrees

tatiyna

Answer: 304.6°

Step-by-step explanation:

First of all, using the circumference of the circle formula to find the radius of the circle.

Circumference of the circle = 13, ie

2πr = 13,

r = 13/2π ---------------------------- 1

Now getting the radius of the circle now, you now substitute for this in the formula for finding the length of an arc to get the central angle.

Arc length = 11 , ( 2πr0°/360) or (πr0°/180), so

πr0°/180 = 11 ------------------------ 2

Now solve for 0°, the central angle of the angle by making it the subject of the formula.

πr0° = 180 x 11

0° = 180 x 11

----------- ----------------- 3

πr

Now, put equation 1 in equation 3 and solve.

0° = 1980

--------

π x 13/2π

= 1980 x 2π

-----------

π.x. 13

= 1980 x 2

----------

= 3960/13

= 304.6°

Therefore, the central angle of the arc is 304.6°

Please be meticulous and understand the way I change the r in the denominator. It was the rule in fraction when dividing.

5 0

3 years ago