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3 years ago

Help please? not sure about this

Mathematics

1 answer:

zimovet [89]3 years ago

8 0

9514 1404 393

Answer:

72 kph

Step-by-step explanation:

The first sentence tells you the speeds are proportional. So, you can write the proportion ...

kph/mph = 120/75 = x/45

Multiplying by 45 gives x:

x = (45)(120/75) = 72

72 kph is 45 mph.

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Which of the following triangle cases may have one, two, or zero solutions?

Lunna [17]

I think the correct answer is B. It is the triangle case SSA that may have one, two, or zero solutions. This case can have either number of solutions but it depends on the sides of the triangle given. Having one solution can be all of the cases except SSS, having 2 solutions can only be applied to SSA.

6 0

3 years ago

A student gets 68 marks n therefore gets 85 percent total marks are?

mihalych1998 [28]

Answer:

There are 80 marks in total.

Step-by-step explanation:

Let the number of total marks be $x$ .

The percentage score of the student can be written as the ratio

$\displaystyle \frac{68}{x} = 85\%$ .

However,

$\displaystyle 85\% = \frac{85}{100}$ .

Equating the two:

$\displaystyle \frac{68}{x} = \frac{85}{100}$ .

Cross-multiply (that is: multiple both sides by $100x$ , the product of the two denominators) to get

$85x = 68\times 100$ .

$\displaystyle x = \frac{68\times 100}{85} = 80$ .

In other words, there are 80 marks in total.

4 0

3 years ago

Three runners are training for a marathon. One day, they all run about ten miles, each at their own constant speed. Which of the

kotykmax [81]

Answer:

Runner 1 has the fastest pace

Step-by-step explanation:

The first one we need to find the slope

m = (y2-y1)/(x2-x1) = (40-0)/(4-0) =40/4 = 10 minutes per mile

The second is 8.5 minutes per mile

The third we need to find the slope

m = (y2-y1)/(x2-x1) = (90-72)/(10-8) =18/2 = 9 minutes per mile

6 0

3 years ago

Read 2 more answers

Which one is longer 60 inches or 9 feet please help me.Thanks!

kolezko [41]

9 feet is longer. hope thins helps :-)

5 0

3 years ago

Read 2 more answers

An object is dropped from a small plane. As the object falls, its distance, d, above the ground after t seconds, is given by the

DedPeter [7]

The inequality can be used to find the interval of time taken by the object to reach the height greater than 300 feet above the ground is:

$d = -16t^2 + 1000$

Solution:

The object falls, its distance, d, above the ground after t seconds, is given by the formula:

$d = -16t^2 + 1000$

To find the time interval in which the object is at a height greater than 300 ft

Frame a inequality,

$-16t^2 + 1000 > 300$

Solve the inequality

Subtract 1000 from both sides

$-16t^2 + 1000 - 1000 > 300 - 1000\\\\-16t^2 > -700$

$16t^2 < 700\\\\Divide\ both\ sides\ by\ 16\\\\t^2 < \frac{700}{16}\\\\Take\ square\ root\ on\ both\ sides\\\\t < \sqrt{\frac{700}{16}}\\\\t < \pm 6.61$

Time cannot be negative

Therefore,

t < 6.61

And the inequality used is: $-16t^2 + 1000>300$

6 0

3 years ago