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2 years ago

How to solve these? I would like explanation please

Mathematics

1 answer:

GuDViN [60]2 years ago

5 0

Step-by-step explanation:

it is a rectangle. 18m × 4m = 72 m²

the paving costs $35 per m², and we have 72 m², so it does not take a genius to figure out what to do next ...

right : we multiply 35 by 72

35×72 = $2520

10.

how much volume is a liter ?

a liter fits into a cube of 10cm side length.

and 1 meter = 100 cm = 10×10cm.

so, 1 m³ = 10×10×10 = 1000 such cubes of 10cm side length = 1000 liters.

the pool is 5 m × 15 m × 1.5 m = 112.5 m³ = 112500 liters

we need 2 kg salt for every 10000 liters water, so we have how many units of 10000 liters in the pool ?

112500 / 10000 = 11.25

so, we need

11.25 × 2 = 22.5 kg salt

11.

12 seconds = 1/5 of a minute.

so, batman runs at 3 km / min (= 60×3 km/hour = 180 km/h - not possible in real life for any human being, but let's play ...) for 12 seconds = 1/5th of a minute, and so he runs 3km/5 = 600 meters in that time.

that means he has 2km - 600m = 1400m left to run in the 2 km race.

it takes him 1400/3000th of a minute (3000 m would take him the full minute)

1400 m × minute / 3000 m = 14/30 = 7/15 minutes

1/15th minute = 60 seconds / 15 = 4 seconds.

so, 7/15th of a minute = 7×4 seconds = 28 seconds.

the bionic woman runs the full 2000 m with 5 km / minute.

it takes her 2000/5000th of a minute

2000 m × minute / 5000 = 2/5th of a minute.

1/5th of a minute is 60 seconds / 5 = 12 seconds.

so, 2/5th of a minute is 12×2 = 24 seconds.

therefore, the bionic woman wins by 4 seconds (24 seconds vs. 28 seconds).

12.

there is enough food for 150 students for 5 days = 150×5 =750 "food units".

therefore, if there were only 100 students, the food would last 750/100 = 7.5 days.

and if the food runs out after 4 days it means there are

750/4 = 187.5 students (how much sense that makes to have half a student ...).

13.

x = the workload to be done

Michelle's work speed is x/6 days

Danielle's work speed is x/4 days

on each day working together they achieve

1× x/6 + 1× x/4 of the total work load.

that is

2x/12 + 3x/12 = 5x/12

so, they need 5x/12 × a days to finish the whole x.

5x/12 × a = x

5/12 × a = 1

5a = 12

a = 12/5 = 2.4 days to finish the whole work when working together.

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A bag had 7 orange rocks , 6 green rock , 1 white rock ,7 black rocks , and 2 yellow you randomly pull a rock from the bag ,keep

daser333 [38]

Answer:

$Probability = \frac{7}{253}$

Step-by-step explanation:

Given

$Orange = 7$

$Green = 6$

$White = 1$

$Black = 7$

$Yellow = 2$

Required

Probability of selecting a yellow then orange rock

From the question, we understand that the probability is that of without replacement.

Since the yellow, is first picked.

We need to determine the probability of picking a yellow rock, first.

$P(Yellow) = \frac{n(Yellow)}{Total}$

$P(Yellow) = \frac{2}{7 + 6 + 1 + 7 + 2}$

$P(Yellow) = \frac{2}{23}$

The rock has reduced by 1;

Next is to determine the probability of picking an orange rock

$P(Orange) = \frac{n(Orange)}{Total - 1}$

$P(Orange) = \frac{7}{7 + 6 + 1 + 7 + 2- 1}$

$P(Orange) = \frac{7}{22}$

The required probability is calculated as thus:

$Probability = P(Yellow) * P(Orange)$

$Probability = \frac{2}{23} * \frac{7}{22}$

$Probability = \frac{14}{506}$

$Probability = \frac{7}{253}$

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3 years ago

Directions: Find the indicated trigonometric ratio as a fraction in simplest form. 1. Sin L =

Rainbow [258]

Answer:

$\sin L = 0.60$

$tan\ N = 1.33$

$\cos L = 0.80$

$\sin N = 0.80$

Step-by-step explanation:

Given

See attachment

From the attachment, we have:

$MN = 6$

$LN = 10$

First, we need to calculate length LM,

Using Pythagoras theorem:

$LN^2 = MN^2 + LM^2$

$10^2 = 6^2 + LM^2$

$100 = 36 + LM^2$

Collect Like Terms

$LM^2 = 100 - 36$

$LM^2 = 64$

$LM = 8$

Solving (a): $\sin L$

$\sin L = \frac{Opposite}{Hypotenuse}$

$\sin L = \frac{MN}{LN}$

Substitute values for MN and LN

$\sin L = \frac{6}{10}$

$\sin L = 0.60$

Solving (b): $tan\ N$

$tan\ N = \frac{Opposite}{Adjacent}$

$tan\ N = \frac{LM}{MN}$

Substitute values for LM and MN

$tan\ N = \frac{8}{6}$

$tan\ N = 1.33$

Solving (c): $\cos L$

$\cos L = \frac{Adjacent}{Hypotenuse}$

$\cos L = \frac{LM}{LN}$

Substitute values for LN and LM

$\cos L = \frac{8}{10}$

$\cos L = 0.80$

Solving (d): $\sin N$

$\sin N = \frac{Opposite}{Hypotenuse}$

$\sin N = \frac{LM}{LN}$

Substitute values for LM and LN

$\sin N = \frac{8}{10}$

$\sin N = 0.80$

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kari74 [83]

Answer:

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2 years ago

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Lesechka [4]

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3 years ago

Triangle KJL is inscribed in semicircle O shown below such that JK=6 and JL=11. Which of the following is closest to the radius

lakkis [162]

Uhh, answer choices?

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