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3 years ago

Explain how to find 40*50 using mental math?

Mathematics

2 answers:

SCORPION-xisa [38]3 years ago

5 0

Answer:

See Explanation

Step-by-step explanation:

We see that $40=4*10\\50=5*10$ . We can use this to find that $40*50=4*5*10*10=20*100=2,000$ .

umka21 [38]3 years ago

4 0

Answer:

2000

Step-by-step explanation:

x 50

______

you multiply the 0 by 0 which is 0 and then you multiply the 0 by 4 and thats zero. then you multiply 5 by zero and then multiply five by 4 which is 20. that gives you 2000.

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Write a paragraph that has an inverted triangle shape. The topic sentence should be, “Trees are helpful.” Include at least three

SashulF [63]

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3 years ago

Which of the following is an example of how a scientist might use a model?

igomit [66]

The end of a slinky is moved vertically up and down to simulate a wave.

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3 years ago

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Jesse and Amir were assigned the same book to read. Jesse started reading on Saturday, and he is reading 30 pages a day. Amir di

bezimeni [28]

1. An equation representing the number of days Amir has been reading and the number of pages he has read is <u>y = 35x</u>.

2. An equation representing the number of days Jesse has been reading and the number of pages she has read is <u>y = 30 + 30x</u>.

3. The system of equations from 1 and 2 is y = 35x and y = 30 + 30x.

4. At the end of Friday, after solving the equations, both Jesse and Amir read <u>210 pages each</u>, with Jesse spending <u>7 days</u> and Amir <u>6 days</u>.

5. For Jesse and Amir, the equation solutions are <u>y is 210</u> pages and <u>x is 6 days</u>.

6. After solving the equations, it will take Amir <u>6 days</u> to catch up with Jesse and each person must have read <u>210 pages</u> or a total of <u>420 pages</u>.

<h3>What is a system of equations?</h3>

A system of equations involves using more than one equation solved simultaneously.

Jesse's reading rate per day = 30 pages

Amir's reading rate per day = 35 pages

The number of pages read by Jesse, y = 30 + 30x

The number of pages read by Amir, y = 35x

Where x = the number of days they have been reading

<h3>Solving the equations:</h3>

y = 30 + 30x and y = 35x

35x = 30 + 30x

35x - 30x = 30

5x = 30

x = 6 (30/5)

<h3>Jesse:</h3>

y = 30 + 30x

y = 30 + 30(6)

y = 210

y = 35x

y = 35(6)

y = 210

Learn more about simultaneous equations at brainly.com/question/16763389

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1 year ago

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Grace [21]

The answer would be C since you have to distribute hope I helped

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3 years ago

Read 2 more answers

If 1 cm represents 30 km on a map and colorado is shown by a 20cm by 15 cm rectangle on the map, what is the approximate actual

zubka84 [21]

Answer:

20*30km = 600km

15*30km = 450km

600km * 450km = 270000 km^2

Step-by-step explanation:

assuming 1cm --- 30km causes that 2cm --- 60km, 3cm --- 90km, 4cm --- 120km etc. Notice that number of km's is 30 times greater than the number of cm's on a map

using this logic, you calculate both real dimensions of Colorado by multiplying 20*30 = 600 km and 15*30 = 450km

Then we use a formula of an area of a rectangle $A=a\cdot b$ assuming $a=600km, \ b=450km$ and get $A=600\cdot 450=270000km^2$ which is an actual area of Colorado

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3 years ago