Lizzie has 18 dimes and 12 quarters
<em><u>Solution:</u></em>
Let "d" be the number of dimes
Let "q" be the number of quarters
We know that,
value of 1 dime = $ 0.10
value of 1 quarter = $ 0.25
Given that LIzzie has 30 coins
number of dimes + number of quarters = 30
d + q = 30 ---- eqn 1
Also given that the coins total $ 4.80
number of dimes x value of 1 dime + number of quarters x value of 1 quarter = 4.80
0.1d + 0.25q = 4.8 ------ eqn 2
Let us solve eqn 1 and eqn 2
From eqn 1,
d = 30 - q ---- eqn 3
Substitute eqn 3 in eqn 2
0.1(30 - q) + 0.25q = 4.8
3 - 0.1q + 0.25q = 4.8
0.15q = 1.8
<h3>q = 12</h3>
From eqn 3,
d = 30 - 12
<h3>d = 18</h3>
Thus she has 18 dimes and 12 quarters
Answer:
A stone is thrown straight up from the edge of a roof, 750 feet above the ground at a speed of 14 feet per second. A) Remembering that the acceleration due to gravity is -32 feet per second squared, how high is the stone 2 seconds later? B) At what time does the stone hit the ground? C) What is the velocity of the stone when it hits the ground?
Step-by-step explanation:
A stone is thrown straight up from the edge of a roof, 750 feet above the ground at a speed of 14 feet per second. A) Remembering that the acceleration due to gravity is -32 feet per second squared, how high is the stone 2 seconds later? B) At what time does the stone hit the ground? C) What is the velocity of the stone when it hits the ground?
The technique of matrix isolation involves condensing the substance to be studied with a large excess of inert gas (usually argon or nitrogen) at low temperature to form a rigid solid (the matrix). The early development of matrix isolation spectroscopy was directed primarily to the study of unstable molecules and free radicals. The ability to stabilise reactive species by trapping them in a rigid cage, thus inhibiting intermolecular interaction, is an important feature of matrix isolation. The low temperatures (typically 4-20K) also prevent the occurrence of any process with an activation energy of more than a few kJ mol-1. Apart from the stabilisation of reactive species, matrix isolation affords a number of advantages over more conventional spectroscopic techniques. The isolation of monomelic solute molecules in an inert environment reduces intermolecular interactions, resulting in a sharpening of the solute absorption compared with other condensed phases. The effect is, of course, particularly dramatic for substances that engage in hydrogen bonding. Although the technique was developed to inhibit intermolecular interactions, it has also proved of great value in studying these interactions in molecular complexes formed in matrices at higher concentrations than those required for true isolation.
Answer:
amount of interest = 52.5
amount at the end of the period = 1052.5
Step-by-step explanation:
use the formula for simple interest
PRT/100
P is the principle
R is the rate of interest charged
T is the Time taken
18 months = 1 years 6 months ( 1.5 years)
1000 * 3.5 * 1.5 = 5250
5250/100 = 52.5
the amount of interest = <u>52.5</u>
the amount she will have at the end of the period
= 1000 +52.5
= <u>1052.5</u>
