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4 years ago

Not good with word problems please help

Mathematics

1 answer:

Zepler [3.9K]4 years ago

5 0

Let a and b be the respective rates in bricks per minute for Alex and Bob separately.

Alex lays 4 bricks per minute more than Bob

a = b + 4

Working together, their rates scale by 3/4 and they achieve 15 bricks per minutes.

(3/4)(a + b) = 15

Two equations, two unknowns, we solve:

b = a - 4

(3/4)(a + a - 4) = 15

2a - 4 = (4/3) 15 = 20

2a = 24

a = 12

b = a - 4 = 8

Answer: Alex alone does 12 bricks per minute, Bob alone 8 bricks per minute

Check: a=b+4, good

(3/4)(12 +8)=(3/4)(20)=15, good

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A diver went 25.65 feet below the surface of the ocean and then 16.5 feet further down he then rose 12.45 feet write and solve a

Anastaziya [24]

So a diver went 25.65 ft BELOW so it's negative.
then he went 16.5 ft further down, so that's negative also.
he then rose 12.45 ft, so that's positive.
so the expression is: -25.65+-16.5+12.45, the answer is 23.7

8 0

3 years ago

Lisa earns $8 an hour. How many hours must she work to earn $272? * L. M. N.

elena-14-01-66 [18.8K]

Answer:

34 hours

Step-by-step explanation:

I got that by dividing 272 and 8 and you would get 272 is you multiply 8 times 34

4 0

3 years ago

Read 2 more answers

Janelle made a fruit cake using bananas and apples. Forty percent of fruits are bananas. If she used a total of 120 fruits, how

babymother [125]

40% of 120 is 48, so she used 48 bananas.

120 - 48 = 72

So she should use 72 apples.

7 0

3 years ago

(section 6.1) Find the length of the small arc formed by the intersection of the unit circle a circle centered at the origin wit

Nikitich [7]

Answer:

The length of the arc is approximately 2.0944

Step-by-step explanation:

The given parameters are;

The equation of the circle = x² + y² = 1

The radius of the circle, r = 1

The equation of the line, y = 1/2

Therefore, we point where the line intersects with the circle are given as the points 'y = 1/2' as follows;

When y = 1/2, the equation of the circle becomes;

x² + (1/2)² = 1

x² = 1 - (1/2)² = 3/4

x = ±√3/2

The angle subtended by the arc, θ = 2 × arctan((√3/2)/(1/2)) = 120°

The circumference of the circle, C = 2·π·r

∴ C = 2 × π × 1 = 2·π

The length of the arc, l = (θ/360) × C

∴ l = (120/360) × 2·π = (2/3)·π

The length of the arc, l = (2/3)·π ≈ 2.0944

8 0

3 years ago

One diagonal of a rhombus has endpoints (-11, -9) and (-5, -3).

valina [46]

Answer:

(-10, -8) and (-6, -4)

Step-by-step explanation:

we know that

The diagonals of a rhombus are perpendicular

If two lines are perpendicular, then the product of their slopes is equal to -1

m1*m2=-1

step 1

Find the slope of the given diagonal

we have

(-11, -9) and (-5, -3)

m=(-3+9)/(-5+11)

m=-6/6=-1

Find the slope of the other diagonal

we have

m1=-1

Find m2

m1*m2=-1

(-1)*m2=-1

m2=1

step 2

Verify the slope of each of the endpoints of the other diagonal

The slope of the other diagonal must be equal to 1

case a) (-10, -4) and (-6, -8)

m=(-8+4)/(-6+10)

m=-4/4=-1

therefore

The points of case a) cannot be the end-points of the other diagonal

case b) (-8, -3) and (-5, -6)

m=(-6+3)/(-5+8)

m=-3/3=-1

therefore

The points of case b) cannot be the end-points of the other diagonal

case c) (-8, -4) and (-8, -8)

m=(-8+4)/(-8+8)

m=-4/0 -----> undefined

therefore

The points of case c) cannot be the end-points of the other diagonal

case d) (-10, -8) and (-6, -4)

m=(-4+8)/(-6+10)

m=4/4=1

therefore

The points of case d) can be the end-points of the other diagonal

6 0

3 years ago