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1 year ago

27 solid iron spheres,each of radius x cm are melted to form a sphere with radius y cm ,find the ratio of x:y

Mathematics

1 answer:

madam [21]1 year ago

7 0

Radius of 1 solid iron sphere =r

→ Volume =34πr3

→ Volume of 27 solid iron

spheres =27x34πr3

→ 34πr'3=27x34πr3

r'3=2πr3

→r'=3r

(ii) Surface area =4+πr2

SA r'=4πr'2

=4π(3r)2=36πr2

S'S=36πr24πr2=91=1:9

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Answer:

Option (2)

Step-by-step explanation:

Option (1)

In the interval [-1, 1] Or -1 ≤ x ≤ 1, value of the function will be represented by the y-values.

Since, the graph is below x-axis in the interval -1 ≤ x ≤ 0.5, function will be negative.

And in the interval 0.5 ≤ x ≤ 1, graph is above the x-axis, function will be positive.

Option (2)

In this option, graph is below the x-axis in the interval [-1, 1].

Therefore, the given graph is negative in this interval.

Option (3)

In this graph, function is negative and positive both in the interval -1 ≤ x ≤ 1.

Option (4)

In this graph function is completely above the x-axis in the interval -1 ≤ x ≤ 1.

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3 years ago

Why is water so important to living organisms

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2 years ago

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Will a 9/32 inch diameter pin fit into a reamed hole with a diameter of 0.278 inch? (Do not round off your answer and express it

ollegr [7]

Answer:

9/32 inch diameter pin will not fit into a reamed hole with a diameter of 0.278 inch

Step-by-step explanation:

Diameter of reamed hole = 0.278 inch

Radius of reamed hole = $\frac{0.278}{2} =0.139$

Surface area of reamed hole = $\pi r^2$

Surface area of reamed hole = $3.14 \times (0.139)^2$

Surface area of reamed hole = 0.06066794

Diameter of pin = $\frac{9}{32}$

Radius of pin = $\frac{9}{64}$

Surface area of pin = $\pi r^2 = 3.14 \times ( \frac{9}{64})^2=0.0620$

Since the surface area of pin is more than the surface area of hole .

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3 years ago

In a random sample of 200 students, 55% indicated they have full-time jobs, while the other 45% have part-time jobs. Fifty of th

Zigmanuir [339]

Answer:

The probability is $\frac{5}{9}$

Step-by-step explanation:

The total number of students are 200.

number of full timers is 110 and number of part timers is 90.

number of male students is 90 and number of female students is 110.

Let the probability of part timers be P(B).

P(B) = $\frac{90}{200}$ = $\frac{9}{20}$

Let the probability of female part timers be P(A)

P(A) = $\frac{50}{200} = \frac{5}{20}$

now, the final probability is

= $\frac{P(A)}{P(B)}$

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3 years ago

Jess deposited $5,000 into an account that earns simple interest. After 9 years, Jess had earned $3,150 in interest. What was th

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Answer:

The interest rate of Jess's account was 7%

Step-by-step explanation:

A = P * (1 + rt)

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P = initial principal balance

r = annual interest rate

t = time (in years)

Replacing with the values we know:

A = P * (1 + rt)

8,150 = 5,000 * (1 + r * 9)

8,150/5,000 = 1 + 9r

1.63 = 1 + 9r

1.63 - 1 = 9r

0.63 = 9r

r = 063/9

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The interest rate of Jess's account was 7%

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2 years ago

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