Let d = number of dimes, q = number of quarters
<span>Sally has 20 coins in her piggy bank, so </span>
<span>d + q = 20 </span>
<span>The total amount of money is $3.05. </span>
<span>Use the value of each coin multiplied by its number to get total value </span>
<span>.10d + .25q = 3.05 </span>
<span>multiply everything by 100 to clear the decimal places </span>
<span>10d + 25q = 305 and </span>
<span>d + q = 20 </span>
<span>solve the second equation above in terms of either d or q - lets do d </span>
<span>d = 20 - q </span>
<span>sub that into the first equation </span>
<span>10d + 25q = 305 </span>
<span>10(20 - q) + 25q = 305 </span>
<span>200 - 10q + 25q = 305 </span>
<span>15q = 105 </span>
<span>q = 105/15 = 7 </span>
<span>and from above </span>
<span>d = 20 - q = 20 - 7 = 13 </span>
<span>so, there are 13 dimes and 7 quarters </span>
<span>verify with orig problem </span>
<span>13 + 7 = 20, OK, and $1.30 + $1.75 = $3.05
</span>
Answer:
a = 2
Step-by-step explanation:
In an AP the difference between consecutive terms is common (equal), thus
t₂ - t₁ = t₃ - t₂ , that is
2a + 1 - (a + 1) = 4a - 1 - (2a + 1) ← distribute and simplify both sides
2a + 1 - a - 1 = 4a - 1 - 2a - 1
a = 2a - 2 ( subtract 2a from both sides )
- a = - 2 ( multiply both sides by - 1 )
a = 2
pls mark as brainlist
Step-by-step explanation:
624 divided by 8 = 78
If there is 10% of $18 = 18 x 0.9 (1 - 0.1) = $16.20
Therefore the pie costs $16.20
He is saving 18 - 16.20 = $1.80
