Percentages and ratios: Maths KS3
In lessons three and four, use algebra to calculate how fast a Tunnel Boring Machine (TBM) can bore through the ground, and use percentages and ratios to explore how rainfall across London drains into four Combined Sewer Overflows (CSOs).
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Maths KS3 Lesson 4: Percentages and ratios
Screen 3: With the new Tunnel, these overflows will be intercepted and diverted into the Tunnel and then pumped out for treatment, via the Lee Tunnel at Beckton sewage treatment works.
Screen 4: We can model how rainfall flows through each CSO and into the Tunnel. What can this table tell you about the effect of rainfall on water flow into the Tunnel?