7th Grade Math Review worksheet featuring proportion problems and an answer bank for solving.

Let’s solve each proportion step by step. Remember: in a proportion like $\frac{a}{b} = \frac{c}{d}$, you can cross-multiply to get $a \cdot d = b \cdot c$. Then solve for the missing variable.

---

Problem #1:
$\frac{x}{6} = \frac{13}{39}$

Cross-multiply:
$x \cdot 39 = 6 \cdot 13$
$39x = 78$

Divide both sides by 39:
$x = \frac{78}{39} = 2$

✔ Answer: 2

---

Problem #2:
$\frac{7}{x} = \frac{4}{12}$

Cross-multiply:
$7 \cdot 12 = 4 \cdot x$
$84 = 4x$

Divide both sides by 4:
$x = \frac{84}{4} = 21$

✔ Answer: 21

---

Problem #3:
$\frac{24}{36} = \frac{x}{54}$

Cross-multiply:
$24 \cdot 54 = 36 \cdot x$
Calculate $24 \cdot 54$:
$24 \cdot 50 = 1200$, $24 \cdot 4 = 96$, so $1200 + 96 = 1296$
So: $1296 = 36x$

Divide both sides by 36:
$x = \frac{1296}{36}$

Let’s divide:
$36 \cdot 30 = 1080$, subtract from 1296 → 216 left
$36 \cdot 6 = 216$, so total is $30 + 6 = 36$

✔ Answer: 36

---

Problem #4:
$\frac{15}{27} = \frac{60}{x}$

Cross-multiply:
$15 \cdot x = 27 \cdot 60$

Calculate $27 \cdot 60$:
$27 \cdot 6 = 162$, so $27 \cdot 60 = 1620$
So: $15x = 1620$

Divide both sides by 15:
$x = \frac{1620}{15}$

Divide:
$15 \cdot 100 = 1500$, subtract → 120 left
$15 \cdot 8 = 120$, so $100 + 8 = 108$

✔ Answer: 108

---

Problem #5:
$\frac{76}{x} = \frac{19}{20}$

Cross-multiply:
$76 \cdot 20 = 19 \cdot x$

Calculate $76 \cdot 20 = 1520$
So: $1520 = 19x$

Divide both sides by 19:
$x = \frac{1520}{19}$

Let’s divide:
$19 \cdot 80 = 1520$ (because $19 \cdot 8 = 152$, so times 10 is 1520)

✔ Answer: 80

---

Problem #6:
$\frac{x}{78} = \frac{30}{45}$

First, simplify $\frac{30}{45}$ → divide numerator and denominator by 15 → $\frac{2}{3}$

So now: $\frac{x}{78} = \frac{2}{3}$

Cross-multiply:
$3x = 2 \cdot 78 = 156$

Divide both sides by 3:
$x = \frac{156}{3} = 52$

✔ Answer: 52

---

Now let’s list all answers:

#1: 2
#2: 21
#3: 36
#4: 108
#5: 80
#6: 52

Check against answer bank:
Available numbers: 2, 5, 21, 36, 52, 78, 80, 84, 108 — we used: 2, 21, 36, 108, 80, 52 → all are in the bank. Perfect!

Final Answer:
2, 21, 36, 108, 80, 52