Hi!
You can easily apply the Rule of Three.
1. Known data:
20 pages typed (a) ............................ in 2 hours (b)
380 pages will be typed (c) ............ in X hours
2. Unknown data: X
3. Application of the Rule of the Three:
![X = (bc)/(a)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/an7ooh7g5bctbt3n5pvbd89i4roxow12og.png)
X = (380 x 2) / 20X = 760 / 20
X = 38
4. Conclusion:
Miss Reyes will finish typing the full manuscript of 380 pages within 38 hours.