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A bag contains only apple and oranges. The probability an apple is picked randomly is 1 in 5. The apple is returned, and ﬁve more apples are added to the bag. The probability of an apple being picked is now 1in 3. How many apples were there originally?

2 simultaneous unknown equations. Let x be the number of apples originally, and n the number of fruits in the bag in total originally. i) first scenario, where probability is 1/5, x/n = 1/5 5x= n ii) ...

Answered by Chloe L. • Maths tutor

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Describe how a nerve impulse travels from neurone A to neurone B.

As an action potential arrives at A (the presynaptic terminal), pre-formed vesicles containing a chemical neurotransmitter fuse with the presynaptic membrane, releasing the chemical neurotransmitter into ...

Answered by Medani E. • Biology tutor

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solve this simultaneous equation: 2x + 3y = 19 (Eq1) and 3x + y = 11 (Eq2)

Begin by multiplying the second equation by three in order to get a 3y value: 9x + 3y = 33. We can now subtract equation one from equation two, 9x + 3y = 33 and 2x + 3y = 19 -->7x + 0y = 14. Resulting ...

Answered by Tomas B. • Maths tutor

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In the flowing equitation 2H2+O2→2H2O how many grams of oxygen are needed to make 9g of water?

2H₂+O₂->2H₂OThe best way to answer any mass balancing questions like this is to set the information in a table as follows and fill in the blanks: 2H₂+ O

Answered by Caroline O. • Chemistry tutor

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Describe how elements are arranged in the periodic table

Elements in the periodic table are arranged in order of increasing atomic (proton) number. Elements with the same number of electron shells are arranged in the horizontal rows (periods), and elements with...

Answered by Georgia C. • Chemistry tutor

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