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3 years ago

8

Kaley's family drove to DisneyLand for spring break. Her mom and dad shared the driving duties for a total of 24 hours. Her mom

drove 75 miles per hour, and her dad drove 60 miles per hour. If they drove a total of 1,710 miles, how many hours did each person drive for?

1 answer:

qaws [65]3 years ago

3 0

Answer:

Mom drove for 18 hours.

Dad drove for 6 hours.

Step-by-step explanation:

Given that:

Number of hours for the driving duty = 24 hours

Speed at which the mom drove = 75 miles per hour

Speed at which the dad drove = 60 miles per hour

Total distance driven by both of them = 1710 miles

To find:

Number of hours for which each person drive for ?

Solution:

Let number of hours driven by dad = $x$ hours

Let number of hours driven by mom = (24 - $x$ ) hours

Let us have a look at the formula for Distance in terms of Speed and Time.

$Distance = Speed \times Time$

Distance traveled by Mom = $75 \times x =75x \ miles$

Distance traveled by dad = $60(24-x) =144-60x$ miles

As per question statement:

$75x+1440-60x=1710\\\Rightarrow 15x=1710-1440\\\Rightarrow 15x = 270\\\Rightarrow x = 18\ hours$

So, Mom drove for 18 hours.

Dad drove for 6 hours.

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weqwewe [10]

X -<span> length of a leg

1/2*x</span> - <span>length of the base

so:

$P=2\cdot x+\dfrac{1}{2}x\\\\\\50=2x+\dfrac{1}{2}x\\\\\\50=2\dfrac{1}{2}x\\\\\\50=\dfrac{5}{2}x\quad|\cdot\dfrac{2}{5}\\\\\\x=50\cdot\dfrac{2}{5}\\\\\\x=\dfrac{100}{5}\\\\\\\boxed{x=20\text{ cm}}\qquad\qquad\text{(leg)}$

and

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4 years ago

There are 10 2/15 kg of watermelons and coconuts on a truck. The weight of the watermelons is 3 3/5 times that of the coconuts.

JulijaS [17]

Answer:

2 7/76 kg

Step-by-step explanation:

Let the weight of

Watermelons = x

Coconut = y

There are 10 2/15 kg of watermelons and coconuts on a truck.

x + y = 10 2/15

x = 10 2/15 - y

x = 152/15 - y.... Equation 1

The weight of the watermelons is 3 3/5 times that of the coconuts.

x = 3 3/5 × y

x = 18/5 × y

x = 18y/5

How heavy are the coconuts on the truck, in kg?

Find y

We substitute 18y/5 for x in Equation 1

x = 152/15 - y

18y/5 = 152/15 - y

18y /5 + y = 152/15

Multiply through by 15

18y/5 × 15 + y × 15 = 152/15 × 15

3 × 18y + 15y = 152

54y + 15y = 152

69y = 152

y = 152/69

y = 2 14/152

y = 2 7/76 kg

Therefore, the weight of the coconuts are 2 7/76 kg

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3 years ago

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faust18 [17]

Answer:

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Step-by-step explanation:

100+100=200

200-3=197

197+6=203

203-0.5=202.5

202.5+41=243.5

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243.7×2=487.1

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3 years ago

a cookie baker has an automatic mixer that turns out a sheet of dough in the shape of a square 12 inches wide. His cookie cutter

iragen [17]

Answer:

All the sizes that satisfy $kd^2 =144$

Step-by-step explanation:

To answer this question we first need to find the minimum wasted area of the dough.

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and therefore, the number that will fit into the whole square sheet will be

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the area of n^2 cookies will be

$A_n = n^2\pi \frac{d^2}{4}$ ,

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putting in the value of $n^2$ we get

$a^2- \dfrac{a^2}{d^2}\pi \frac{d^2}{4}$

which simplifies to

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putting in a = 12 we get

area left = 30.902 in^2.

Going back to equation (1) we find that

a^2-n^2(πd^2/4) =30.902

12^2- n^2(πd^2/4) =30.902

and if we call k = n^2, we get

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113.098 = k(πd^2/4)

simplifiying this gives

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vekshin1

Answer:

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Step-by-step explanation:

Given:

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$g(x)=x^2+3$

Now, the function 'f(x)' is given as:

$f(x)=g(x+2)$

So, the function 'f(x)' is a transformation of 'g(x)'.

In order to find f(x), we replace 'x' by $(x + 2)$ in the 'g(x)' function equation. This gives,

$g(x+2)=(x+2)^2+3$

Using the identity $(a+b)^2=a^2+b^2+2ab$ , we get:

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Hence the function f(x) is given as:

$f(x)=x^2+6x+12$

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