Multi-Step Ratio and Percent Problems - 7th Grade Math
Card 1 of 25
State the formula for sale price after a discount rate $d$ on original price $p$.
State the formula for sale price after a discount rate $d$ on original price $p$.
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$\text{sale price} = p(1-d)$. Multiply price by $(1 - \text{discount rate})$.
$\text{sale price} = p(1-d)$. Multiply price by $(1 - \text{discount rate})$.
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State the formula for price after a markup rate $m$ on original cost $c$.
State the formula for price after a markup rate $m$ on original cost $c$.
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$\text{new price} = c(1+m)$. Multiply cost by $(1 + \text{markup rate})$.
$\text{new price} = c(1+m)$. Multiply cost by $(1 + \text{markup rate})$.
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A salesperson earns $6%$ commission on $\$500$ in sales. What is the commission?
A salesperson earns $6%$ commission on $\$500$ in sales. What is the commission?
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$\$30$. Calculate $500 \times 0.06 = 30$.
$\$30$. Calculate $500 \times 0.06 = 30$.
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Find the tip on a $\30$ meal at $20%$.
Find the tip on a $\30$ meal at $20%$.
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$\6$. Calculate $30 \times 0.20 = 6$.
$\6$. Calculate $30 \times 0.20 = 6$.
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Find the percent error when $E=52$ and $A=50$.
Find the percent error when $E=52$ and $A=50$.
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$4%$. Calculate $\frac{|52-50|}{50} \times 100% = \frac{2}{50} \times 100%$.
$4%$. Calculate $\frac{|52-50|}{50} \times 100% = \frac{2}{50} \times 100%$.
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State the formula for percent error when experimental is $E$ and accepted is $A$.
State the formula for percent error when experimental is $E$ and accepted is $A$.
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$\frac{|E-A|}{A}\times 100%$. Absolute difference over accepted value, times $100%$.
$\frac{|E-A|}{A}\times 100%$. Absolute difference over accepted value, times $100%$.
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A value drops from $80$ to $60$. What is the percent decrease?
A value drops from $80$ to $60$. What is the percent decrease?
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$25%$. Calculate $\frac{80-60}{80} \times 100% = \frac{20}{80} \times 100%$.
$25%$. Calculate $\frac{80-60}{80} \times 100% = \frac{20}{80} \times 100%$.
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A price rises from $\$40$ to $$50$. What is the percent increase?
A price rises from $\$40$ to $$50$. What is the percent increase?
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$25%$. Calculate $\frac{50-40}{40} \times 100% = \frac{10}{40} \times 100%$.
$25%$. Calculate $\frac{50-40}{40} \times 100% = \frac{10}{40} \times 100%$.
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State the formula for tip amount when bill is $b$ and tip rate is $t$.
State the formula for tip amount when bill is $b$ and tip rate is $t$.
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$\text{tip} = bt$. Tip equals bill times tip rate.
$\text{tip} = bt$. Tip equals bill times tip rate.
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State the formula for percent change from original $o$ to new $n$.
State the formula for percent change from original $o$ to new $n$.
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$\frac{n-o}{o}\times 100%$. Subtract original from new, divide by original, multiply by $100%$.
$\frac{n-o}{o}\times 100%$. Subtract original from new, divide by original, multiply by $100%$.
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State the formula for commission earned when sales are $s$ and commission rate is $r$.
State the formula for commission earned when sales are $s$ and commission rate is $r$.
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$\text{commission} = sr$. Commission equals sales times commission rate.
$\text{commission} = sr$. Commission equals sales times commission rate.
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A store marks up $\$40$ by $15%$. What is the new price?
A store marks up $\$40$ by $15%$. What is the new price?
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$\$46$. Calculate $40 \times 1.15 = 46$.
$\$46$. Calculate $40 \times 1.15 = 46$.
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Identify the decimal form of $35%$.
Identify the decimal form of $35%$.
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$0.35$. Move decimal point two places left to convert percent to decimal.
$0.35$. Move decimal point two places left to convert percent to decimal.
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State the formula for simple interest $I$ when principal is $P$, rate is $r$, and time is $t$.
State the formula for simple interest $I$ when principal is $P$, rate is $r$, and time is $t$.
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$I = Prt$. Simple interest equals principal times rate times time.
$I = Prt$. Simple interest equals principal times rate times time.
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What is the total balance formula $A$ after simple interest $I$ is added to principal $P$?
What is the total balance formula $A$ after simple interest $I$ is added to principal $P$?
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$A = P + I$. Total amount is principal plus interest earned.
$A = P + I$. Total amount is principal plus interest earned.
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What is $18%$ of $50$?
What is $18%$ of $50$?
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$9$. Multiply $50 \times 0.18 = 9$.
$9$. Multiply $50 \times 0.18 = 9$.
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What is the sale price of $\$60$ after a $25%$ discount?
What is the sale price of $\$60$ after a $25%$ discount?
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$\$45$. Calculate $60 \times (1 - 0.25) = 60 \times 0.75$.
$\$45$. Calculate $60 \times (1 - 0.25) = 60 \times 0.75$.
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A $\$50$ bill includes a $10%$ tip. What was the pre-tip bill amount?
A $\$50$ bill includes a $10%$ tip. What was the pre-tip bill amount?
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$\frac{$50}{1.10}$. Divide total by $1.10$ to find original bill.
$\frac{$50}{1.10}$. Divide total by $1.10$ to find original bill.
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What is the total cost after $7.5%$ tax is added to $ \$80 $?
What is the total cost after $7.5%$ tax is added to $ \$80 $?
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$ \$86 $. Add tax to original: $80 + 6 = 86$.
$ \$86 $. Add tax to original: $80 + 6 = 86$.
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Find the percent increase from $50$ to $65$.
Find the percent increase from $50$ to $65$.
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$30%$. Change is $15$, so $\frac{15}{50} \times 100% = 30%$.
$30%$. Change is $15$, so $\frac{15}{50} \times 100% = 30%$.
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State the formula for simple interest when principal is $P$, rate is $r$, and time is $t$.
State the formula for simple interest when principal is $P$, rate is $r$, and time is $t$.
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$I = Prt$. Interest equals principal times rate times time.
$I = Prt$. Interest equals principal times rate times time.
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State the formula for total amount after simple interest using $P$ and interest $I$.
State the formula for total amount after simple interest using $P$ and interest $I$.
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$A = P + I$. Total amount is principal plus interest earned.
$A = P + I$. Total amount is principal plus interest earned.
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What is $15%$ of $80$?
What is $15%$ of $80$?
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$12$. Convert 15% to 0.15, then multiply: $0.15 \times 80 = 12$.
$12$. Convert 15% to 0.15, then multiply: $0.15 \times 80 = 12$.
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What decimal is equivalent to $7%$?
What decimal is equivalent to $7%$?
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$0.07$. Move decimal point two places left: 7% = 0.07.
$0.07$. Move decimal point two places left: 7% = 0.07.
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State the formula for tax amount when price is $p$ and tax rate is $r$ (decimal).
State the formula for tax amount when price is $p$ and tax rate is $r$ (decimal).
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$\text{tax} = pr$. Tax amount is price times tax rate (as decimal).
$\text{tax} = pr$. Tax amount is price times tax rate (as decimal).
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